Alteration 18 Volt Battery Screwdriver

Converting a screwdriver to lithium batteries

Alteration 18 Volt Battery Screwdriver

Many screwdriver owners want to remake batteries from them into lithium battery cells. Many articles have been written on this topic and in this material I would like to summarize information on this issue. First of all, we will consider the arguments in favor of remaking a screwdriver on and against lithium batteries. And also consider some aspects of the battery replacement process itself.

Pros and cons of reworking a lithium cell screwdriver battery

First you need to think about whether I need this alteration? After all, it will be a frank “self-propelled gun” and in some cases can lead to failure of both the battery and the screwdriver itself. Therefore, let’s take a look at the pros and cons of this procedure. It is possible that after this some of you will decide to abandon the alteration of the Ni─Cd battery for a screwdriver on lithium cells.

The pros

Let’s start with the benefits:

  • The energy density of lithium-ion cells is significantly higher than that of nickel-cadmium, which are used by default in screwdrivers. That is, the battery on lithium banks will have less weight than on cadmium banks with the same capacity and output voltage;
  • Charging lithium battery cells is much faster than in the case of Ni─Cd. It will take about an hour to charge them safely;
  • Lithium-ion batteries do not have a “memory effect." This means that they do not need to be completely discharged before being charged.

Now about the shortcomings and difficulties of lithium batteries.

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Cons

  • Lithium battery cells cannot be charged above 4.2 volts and discharged below 2.7 volts. In real conditions, this interval is even narrower. If you go beyond these limits, the battery can be damaged. Therefore, in addition to the lithium cans themselves, you will need to connect and install a charge-discharge controller in the screwdriver;
  • The voltage of one Li – Ion element is 3.6–3.7 volts, and for Ni─Cd and Ni─MH this value is 1.2 volts. That is, there are problems with the assembly of the battery for screwdrivers with a voltage rating of 12 volts. Of the three lithium cans connected in series, you can assemble a battery with a nominal value of 11.1 volts. Out of four ─ 14.8, out of five ─ 18.5 volts and so on. Naturally, the voltage limits during a charge-discharge will also be different. That is, there may be compatibility problems with the converted battery with a screwdriver;
  • In most cases, 18650 cans are used as lithium cells for remodeling. They differ in size from Ni─Cd and Ni─MH cans. In addition, you will need a place for the charge-discharge controller and wires. All this will need to fit in a standard battery case of a screwdriver. Otherwise, it will be extremely inconvenient for them to work;
  • A charger for cadmium batteries may not be suitable for charging the battery after reworking it. You may need to finalize the charger or use universal charges;
  • Lithium batteries lose their capacity at low temperatures. This is critical for those who use a street screwdriver;
  • The price of lithium batteries is higher than cadmium.

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Replacing lithium batteries in a screwdriver

What do you need to estimate before starting work?

It is necessary to determine the number of elements in the battery, which ultimately decides the voltage value. For three elements, the ceiling will be 12.6, and for four ─ 16.8 volts. We are talking about reworking widespread batteries with a nominal value of 14.4 volts. It is better to choose 4 elements, since during operation the voltage will quickly sink to 14.8. The difference in several volts will not affect the work of the screwdriver.

In addition, more lithium cells will provide more capacity. This means a longer working time for the screwdriver.

18650 lithium battery cells

Next, you need to choose the lithium elements themselves. The form factor without options is 18650. The main thing you need to look at is the discharge current and capacity. According to statistics, during the normal operation of the screwdriver, the consumed current is in the range of 5-10 amperes. If you sharply press the start button, the current can jump up to 25 amperes for several seconds. That is, you need to choose 18650 lithium batteries with a maximum discharge current of 20-30 amperes. Then, with a short-term increase in current to these values, the battery will not be damaged.

The nominal voltage of lithium cells is 3.6–3.7 volts, and the capacity in most cases is 2000–3000 mAh. If the battery case allows, you can take not 4, but 8 elements. Connect them in two into 4 parallel assemblies, and then connect them in series. As a result, you can increase the battery capacity. But not every case will be able to pack 8 cans of 18650.

And the last preparatory stage is the choice of the controller. According to its characteristics, it must correspond to the rated voltage and discharge current. That is, if you decide to collect a 14.4 volt battery, then choose a controller with this voltage. The working discharge current is usually chosen to be half as much as the maximum permissible current.

Charge / Discharge Controller Board

We have established above that the maximum permissible short-time discharge current for lithium cells is 25–30 amperes. So, the charge-discharge controller should be designed for 12-15 amperes. Then the protection will be triggered when the current increases to 25-30 amperes. Do not forget about the dimensions of the protection board. It, together with the elements, will need to be placed in the battery case of the screwdriver.

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Battery Replacement

Well, then comes the assembly process itself. First disassemble the battery case. If this is a 14.4 volt model, then inside there will be 12 nickel cadmium batteries with a nominal value of 1.2 volts.

Assembly of Nickel Cadmium Batteries

All this garland needs to be unsoldered or bitten off. You should only have a connector with a positive and negative output. The temperature sensor can also be removed, and instead choose a controller with a thermocouple, which will turn off the banks when overheating.

After that, you need to solder the purchased items into an assembly with a serial connection. Next, the controller is soldered to it in accordance with its scheme. In this case, balancing points are connected. The board has a special connector for them, and often wires with a connector are supplied.

Screwdriver Battery Housing

After assembling the battery, the plus and minus conclusions are soldered, and the entire structure is placed in the case. In principle, the process is over. Problems can only occur with the charger. But in most cases, regular charging for screwdrivers charge lithium cells without problems. In this case, the charge of the cans goes through the controller, so nothing wrong with the elements themselves will not happen.

On the network you can find recommendations for saving on the controller board. That is, the model is bought cheaper, designed for less current. And so that it does not limit the work of the screwdriver, the discharge is done not through the controller, but directly from the cans. And their charging, as expected, goes through the controller.

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do-it-yourself alteration of a screwdriver on a Li-ion without BMS

Many craftsmen have a cordless screwdriver in the service. Over time, the battery degrades and holds less and less charge. Battery deterioration greatly affects battery life. Constant recharging does not help. In this situation, "repackaging" the battery with the same elements helps. The most commonly used items in screwdriver batteries are the size type “SC”. But the most valuable thing from the master is DIY repair.
Redo a screwdriver with a battery of 14.4 volts. Screwdrivers often use a motor for a wide range of supply voltages. So in this case, you can use only three Li-ion cells of 18650 format. I will not use control cards. The discharge of elements will be visible in the work. As soon as the self-tapping screw is not twisted, for example, it is time to put on charging.

Remaking a Li-ion screwdriver without a BMS board

To begin with, we disassemble our battery. Inside it there are 12 elements. 10 pieces in one row and 2 in the second row. A contact group is welded to the second row of elements. We leave a couple of elements with a contact group, the rest is disposed of.Now you need to solder the wires for further work. The contacts turned out to be material that cannot be tinned, so we solder the wires to the elements. Minus to the body of the element, and plus directly to the plus spot. Old elements play the role of support in the work are not involved.I will use lithium-ion batteries of 18650 format. High-current elements are needed for revision. I “dressed” my elements in the heat shrink from Sanyo, the old one was pretty shabby. Checked Imax residual capacity.
We connect the batteries in series and solder the elements of the head. The battery is almost ready.Now we will provide comfortable charging. You need to install the connector on four pins. I applied the connector from the old motherboard to the number of contacts I needed. He took the mate from the old computer power supply.Cut a hole for the connector. Fill the connector with epoxy glue or super glue with soda. Also solder the wires.Solder the wires to the elements. Wire from the first pin of the connector to the plus of the battery. The wire from the second pin of the connector to the plus of the second element, it is the minus of the first element and so on. Since I will charge with a “smart” charger, you need to make a balancing wire.
As a connector for connecting to a charger, I will use a wire from the computer’s power supply. The wire through which the floppy drive was powered. We cut off all the keys from the connector and it fits perfectly under the charger. Soldering simply. Red wire to the first pin of the battery connector. Black wire to the second pin of the battery connector, etc.We connect to the charger and do not forget about the power wires. Our postings are balancing. We install balancing on the charger and wait for a full charge.In such a non-tricky way, you can modify the battery of the shutter for the home.

Watch the video

Remaking Bosch Screwdriver On Lithium

Alteration Cordless screwdriver on lithium cells

Some screwdriver owners want to recycle their batteries into lithium battery cells. Many articles have been written on this topic, and in real material I would like to summarize information on this topic. First, we will examine the reasons for the usefulness of converting a screwdriver on and against lithium batteries. In addition, we consider individual moments of the process of changing the batteries.

Our client is left with and against remaking the cordless screwdriver on lithium cells

First you need to think about whether I need this alteration? This will be a frank “self-propelled gun” and in a number of various cases leads to wear of both the battery and the screwdriver itself. Therefore, it is necessary to consider what remains for our client to do for and against this procedure. It may be that as a result of this, some of you will decide to abandon the alteration of Ni─Cd battery for a screwdriver on lithium cells.

Reasons for

Let’s start with the benefits:

  • The energy density of lithium-ion parts is significantly higher than that of nickel-cadmium, which are usually used in screwdrivers. In other words, the battery on lithium banks has the smallest weight than on cadmium batteries with the same capacity and output voltage;
  • Charging lithium battery parts is much faster than if Ni─Cd passage. It will take about an hour to charge them non-hazardously;
  • In lithium-ion batteries there is no "memory effect". This means that they do not have to be fully discharged before being charged..

Now about the shortcomings and difficulties of lithium batteries.

Reasons Against

  • Lithium battery cells cannot be charged above 4.4.5 volts and discharged below 2.4.7 volts. In real terms, this interval is even narrower. If you go beyond these limits, the battery will of course be disabled. Therefore, apart from the lithium cans themselves, you will need to connect and install a charge-discharge controller in a screwdriver;
  • The voltage of the textbook element Li─Ion is 3.6–3.7 volts, for Ni─Cd and Ni─MH this value is 1.3.5 volts. In other words, it becomes difficult to assemble a rechargeable battery for screwdrivers with a voltage rating of 12 volts. Of the three lithium cans connected in turn, there is an option to assemble a battery with a nominal value of 11.1 volts. Out of four ─ 14.8, out of 5 ─ 18.5 volts, etc. Than what, and the voltage limits during a charge-discharge will also be different. In other words, the comparability of a converted battery with a screwdriver happens;
  • Almost always in the role of lithium parts for alteration, reference banks of 18650 are used. In size they differ from Ni─Cd and Ni─MH cans. Today, you will need a place for a charge-discharge controller and wires. All this will need to fit in the standard battery case of a screwdriver. It will be very awkward to work differently;
  • A cadmium battery charger may not be suitable for charging the battery after reworking it. Maybe it will be necessary to finalize the memory or the introduction of universal charges;
  • Lithium batteries lose their capacity at low temperatures. This is critical for those who use a screwdriver just outside;
  • The cost of lithium batteries is higher than cadmium.

Alteration battery screwdriver BOSCH 12.6V

Read the same

We put lithium into the battery Bosch.

# 122. We translate the BOSCH PSR-12 screwdriver on Li ion battery

Translate batteries screwdriver BOSCH PSR-12 to Li-ion batteries and remake regular charging for Li-ion.

Changing batteries in a lithium screwdriver

What needs to be estimated before work?

It is necessary to determine the number of parts in the battery, which ultimately decides the magnitude of the voltage. For three parts, the ceiling will be 12.6, for four ─ 16.8 volts. We are talking about reworking the widely used batteries with a nominal value of 14.4 volts. It is best to choose 4 elements, since during operation the voltage will quickly sink to 14.8. The difference of several volts will not affect the workplace of the screwdriver.

Already today, more lithium parts will give a huge capacity. And this means a longer working time with a screwdriver.

18650 lithium battery cells

The nominal voltage of lithium parts is 3.6–3.7 volts, and the capacity is almost always 2000–3000 mAh. If the battery case allows, you can take not 4, but 8 parts. Connect them in two into 4 parallel assemblies, and then connect them one by one. And so you can increase the battery capacity. However, it’s far from anyone who can pack 8 cans of 18650.

And the last preliminary step is the choice of controller. In its features, it should correspond to the rated voltage and discharge current. In other words, if you decide to collect a 14.4 volt battery, then choose a controller with this voltage. The working discharge current is usually chosen to be half as much as the maximum permissible current.

Charge / Discharge Controller Board

Read the same

Above, we found that the maximum allowable short-term discharge current for lithium parts is 25-30 amperes. Means, the charge-discharge controller must be designed for 12-15 amperes. Then the protection will be triggered when the current increases to 25-30 amperes. Remember also the dimensions of the protection board. Together with the elements, it will be necessary to fit it into the battery case of the screwdriver.

Battery change

And then comes the assembly process. First, disassemble the battery case. If this is a 14.4 volt model, then inside there will be 12 nickel cadmium batteries with a nominal value of 1.2.4 volts.

Assembly of Nickel Cadmium Batteries

As a result of this, it is necessary to solder the purchased elements into an assembly with an alternate connection. Further, the controller is soldered to it in accordance with its circuit. With all this, balancing points are connected. The board has a special connector for their production, and often the wires with the connector are supplied.

Screwdriver Battery Case

After assembling the battery, the plus and minus conclusions are soldered, and the entire structure is placed in the case. By and large, the process in this matter is over. Obstacles occur only with a charger. However, almost always regular charging for screwdrivers charge lithium cells freely. At the same time, the charge of the cans goes through the controller, so nothing extravagant with the elements themselves will happen.

On the network, there are tips for saving on the controller board. In other words, a cheaper model is bought, designed for the lowest current. And so that it does not limit the work of the screwdriver, the discharge is done not through the controller, but directly from the cans. And their charging, as expected, goes through the controller.

Read the same

Converting a Lithium Battery Screwdriver Charge

Probably the owners of screwdrivers want to recycle their batteries on lithium battery cells. Many articles have been written on this topic, and in real material I would like to summarize information on this topic. First, we will examine the reasons for the usefulness of converting a screwdriver on and against lithium batteries. We also consider individual moments of the process of changing the batteries.

First of all, you should think about whether I need this alteration? This will be a frank “self-propelled gun” and in a number of various cases leads to wear of both the battery and the screwdriver itself. Therefore, it is necessary to consider what remains for our client to do for and against this procedure. You, after which some of you decide to abandon the alteration of Ni─Cd battery for a screwdriver on lithium cells.

  • The energy density of lithium-ion parts is significantly higher than that of nickel-cadmium, which are used in screwdrivers by default. In other words, the battery on lithium banks has the smallest weight than on cadmium batteries with the same capacity and output voltage;
  • Charging lithium battery parts is much faster than the Ni─Cd design is designed for. It will take about an hour to charge them non-hazardously;
  • In lithium-ion batteries there is no "memory effect". This means that they do not need to be completely discharged ahead of time before being charged.

Now about the shortcomings and difficulties of lithium batteries.

  • Lithium battery cells cannot be charged above 4.3.5 volts and discharged below 2.7.7 volts. In real terms, this interval is even narrower. If you go beyond these limits, the battery is an option to disable. Therefore, apart from the lithium cans themselves, you will need to connect and install a charge-discharge controller in a screwdriver;
  • Voltage >textbook element Li─Ion 3.6–3.7 volts, for Ni─Cd and Ni─MH this value is 1.4.5 volts. In other words, there are problems with assembling a rechargeable battery for screwdrivers with a voltage rating of 12 volts. Of the three lithium cans connected in turn, you can assemble a battery with a nominal value of 11.1 volts. Out of four ─ 14.8, out of 5 ─ 18.5 volts, etc. What, what, and the voltage limits during a charge-discharge will also be different. In other words, difficulties arise when comparing a converted battery with a screwdriver;
  • For the most part, 18650 standard cans are used as lithium parts for remaking. They differ in size from Ni─Cd and Ni─MH cans. Today, you will need a place for a charge-discharge controller and wires. All this will need to fit in the standard battery case of a screwdriver. It will be very awkward to work differently;
  • A cadmium battery charger may not be suitable for charging the battery after reworking it. Maybe it will be necessary to finalize the memory or the introduction of universal charges;
  • Lithium batteries lose their capacity at low temperatures. This is critical for those who use an outdoor screwdriver;
  • The cost of lithium batteries is higher than cadmium.

It is necessary to determine the number of parts in the battery, which ultimately decides the magnitude of the voltage. For three parts, the ceiling will be 12.6, for four ─ 16.8 volts. We are talking about reworking the widely used batteries with a nominal value of 14.4 volts. It is best to choose 4 elements, since during operation the voltage will quickly sink to 14.8. The difference of several volts will not affect the workplace of the screwdriver.

THE CHEAPEST RENEWAL OF A CHARGER FOR Lithium Li Ion Batteries

Already today, a lot of lithium parts will give a huge capacity. And this means a longer working time with a screwdriver.

18650 lithium battery cells

The nominal voltage of lithium parts is 3.6–3.7 volts, and the capacity in the bulk is 2000–3000 mAh. If the battery case allows, you can take not 4, but 8 parts. Connect them in two in 4 parallel assemblies, and in the end, connect them one at a time. And so you can easily increase the capacity of the battery. But it’s far from anyone who can pack 8 cans of 18650.

Video: Alteration 18 Volt Battery Screwdriver


And the last preliminary step is the choice of controller. In its features, it should correspond to the rated voltage and discharge current. In other words, if you decide to collect a 14.4 volt battery, then choose a controller with this voltage. The working discharge current is usually chosen to be half as much as the maximum permissible current.

Charge / Discharge Controller Board

Above, we found that the maximum allowable short-term discharge current for lithium parts is 25-30 amperes. Means, the charge-discharge controller must be designed for 12-15 amperes. Then the protection will be triggered when the current increases to 25-30 amperes. Do not forget about the dimensions of the protection board. It, along with the elements will need to fit in the battery case of a screwdriver.

And then comes the assembly process. First, disassemble the battery case. If this is a 14.4 volt model, then inside there will be 12 nickel cadmium batteries with a nominal value of 1.3.5 volts.

Assembly of Nickel Cadmium Batteries

Subsequently, it is necessary to solder the purchased elements into the assembly with alternate connection. Further, the controller is soldered to it, respectively, with its circuit. With all this, balancing points are connected. There is a special connector on the board, and often the wires with the connector are supplied.

We remake the charger of the Interskol 12V screwdriver for Li Ion batteries

Screwdriver Battery Case

After assembling the battery, the plus and minus conclusions are soldered, and the entire structure is placed in the case. By and large, the process in this matter is over. Difficulties only happen with a charger. However, almost always regular charging for screwdrivers charge lithium cells easily. With all this, the charge of the cans goes through the controller, because something special will not happen with the elements themselves.

On the network, we come across tips on saving on the controller board. In other words, a cheaper model is bought, designed for the lowest current. And so that it does not limit the work of the screwdriver, the discharge is done not through the controller, but directly from the cans. And their charging, as expected, goes through the controller.

DIY alteration of a screwdriver battery for lithium

So quite a lot of time has passed since my first alterations of lithium screwdriver batteries. Since then, some experience has been accumulated as a result of the operation of alterations, on the basis of which, and taking into account past shortcomings, I am writing a new instruction.

Choose batteries for reworking a lithium screwdriver.

Firstly, lithium is different. In short, there are Li-Ion batteries for different returns (loads). In our case, batteries with high recoil current are just required. Also, such batteries, as a rule, have an increased charge current, and therefore, having made the correct charge, you can quickly charge the batteries.

I chose these (see photo). This is a 18650 Sony VTC4 (or equivalent) 2100mAh. I took from the Chinese here.

Excellent value for money. High characteristics of recoil and charge currents. The maximum load current is already 30 amperes. Needless to say, in a screwdriver such banks feel great. The capacity is 2100mAh versus the standard 1100mAh (the same capacity (1100mAh) is usually made by factory Li-Ion batteries).

Four cans is for a screwdriver with a rated voltage of 14.4V. For a 12 Volt screwdriver, we take three cans, for example here.

Protection for batteries and rework of the battery controller.

We dealt with the batteries, we continue our alteration of the battery of a screwdriver for Li-ion.

Lithium needs a protection controller. Which will protect the battery banks from overcurrent, overdischarge, overcharge, as well as balance the banks when charging.

Of those that I tried in terms of price and quality, I am more I liked this controller.

It works great. He copes with the load. But there are also disadvantages. Protection is not removed automatically. To remove it, you need to apply voltage to the battery well, or just put it on charge for a couple of seconds.

The second drawback on some screwdrivers can be protection when the trigger is pulled sharply, and in general it is configured not for our banks (which can easily handle currents and more), but based on the datasheet for the key transistors (which are also designed for higher current) of the controller Battery protection can be roughened.

I fixed both flaws as follows.

Finalization of the lithium battery controller. In the picture of the board we see two smd resistors marked R010. Their nominal value is 0.01 Ohm each. They specify at what load current the protection will trip.

I added another same 0.01 ohm resistor to my battery controller, see diagram. You can also add a film capacitor to it, it is just useful so that when you pull the trigger sharply, the protection does not work.

The upper part of the circuit is responsible for the "Power" mode. When the position is on, transistor switches do not work at all and there is no load on them. But also protection. Therefore, this mode is better not to use.

A 15 amp fuse in this mode provides current protection. We put it to your taste. We take the diode more powerfully. I have two pulse diodes in parallel at 6A each (together 12A), something that generally came to hand.

Can connect a small digital voltmeter, for example, such to monitor discharge control.

I connected instead of a voltmeter homemade discharge indicator tuned to 12V. Its operation coincides with the operation of the protection board during normal operation.

Also, for clarity, in parallel with the discharge indicator (in the diagram it is a voltmeter), I connected an LED through a 2K resistor to immediately see when the "Power" mode is on.

I practically do not use the “Power” mode for working with a screwdriver, but I need it to remove the triggered protection. Just switch back and forth and you can twist on.

I took the controller for batteries on 4 banks (a screwdriver with a nominal value of 14.4V) here.

.
Who needs a controller for 3 banks (a screwdriver with a rating of 12V) we take here.

We solder banks according to the scheme below:

I stuffed the whole thing back into the case.

So I got a switch to the "Power" mode. It is also used to reset protection.

Two indicators are located behind. The red LED indicates “Power” mode. Yellow lights up when the "Power" mode is on, when the battery runs down to 12 volts.

Also added a socket. USB with battery voltage. The main thing is that no one mistakenly inserted the phone to recharge 🙂 I use it at a construction site to listen to the adapted receiver and LED lamp.

I’ve been testing a new battery alteration for lithium for a month now, now I like everything. The battery does not sit down for a long time. Shurik easily copes with heavy loads.

One more thing left. Fast charge, as in the top models 🙂

We do home-made charging for a screwdriver converted to a Li-Iion.

I took a DC-DC converter from the Chinese.

You can adjust the output voltage and charging current. It warms decently, but copes.

The output voltage is set to 16.8 V. Current to taste 2-3A. For those who want to keep the batteries 1-2A. We connect a fairly powerful power supply to the input. If the power supply does not produce enough current for your settings on the board, then it will not give out the tuned current.

All placed in the case. I broke the old charge and stuck the top to the new case. There are two small smd LEDs on the board. One is lit when power is applied. The second when charging is in progress. I soldered the LEDs on the wires instead and built them into the charging case.

The connected power is green.

Charging in red on. Since the red LED is more powerful than the green one, during charging the green goes out and only red lights up, when charging is complete the red goes out and the green lights up.

Converting a screwdriver to lithium batteries: instructions

Converting a screwdriver to lithium batteries makes sense. The advantage is that they have a high electrical density. As a result, by installing such a device in the case of a screwdriver, we can achieve an increase in the duration of the tool by many times. The charging current for lithium high-power batteries, especially for new versions, it can reach 1-2 C. It is possible to recharge such a device in 1 hour, without overstating the parameters recommended by the manufacturer and without spoiling the quality of the product.

What do lithium batteries look like?

Most lithium devices are enclosed in a prismatic enclosure, but some models are cylindrical. These batteries use coil electrodes and separators. The case is made of aluminum or steel. The positive pole goes to the housing cover.

In prismatic configurations, the electrodes are in the form of rectangular plates. To ensure safety, the battery provides a device that acts as a regulator of all processes and opens the electrical circuit in critical situations. Increased sealing of the housing prevents the electrolyte from leaking out and penetrating oxygen and moisture.

What precautions should be taken to prevent damage to the lithium battery?

  • Due to technology limitations, the charge indicator of lithium batteries should not be higher than 4.25-4.35 V. The discharge should not reach 2.5-2.7. This condition is indicated in the technical passport for each specific model. If you overstate these values, you can disable the device. Special charge and discharge controllers are used, which keep the voltage on the lithium cell within normal limits. Converting a screwdriver to a lithium battery with a controller will protect the device from a malfunction.
  • The voltage rating of lithium batteries is a multiple of 3.7 V (3.6 V). In Ni-Mh models, this figure is 1.2 V. This phenomenon is understandable. The rated voltage in lithium devices is stored in a separate cell. A 12 volt lithium battery will never be assembled. The rating will be 11.1 V (three consecutive cells) or 14.8 V (four consecutive cells). In addition, the voltage indicator of the lithium cell changes during operation when fully charged by 4.25 V, and when fully discharged by 2.5 V. The voltage indicator 3S (3 serial. three serial connections) will change with the device functioning from 12.6 B (4.2×3) to 7.5 V (2.5×3). For the 4S configuration, this indicator ranges from 16.8 to 10 V.
  • Converting a screwdriver to 18650 lithium batteries (the vast majority of products has this particular size) requires taking into account the difference in dimensions with Ni-Mh cells. The cell diameter of 18,650 is 18 mm and the height is 65 mm. It is very important to calculate how many cells fit in the case. It should be remembered that for a model with a power of 11.1 V, you will need the number of cells that is a multiple of three. For a model with a power of 14.8 V. four. The controller and patch wires should also fit.
  • The charging device for the lithium-based battery differs from the device for Ni-Mh modifications.

The article will consider how the alteration of a screwdriver on lithium Li-Po batteries occurs. The tool is equipped with a pair of Ni-Mh batteries with a voltage rating of 12 V and a capacity of 2.6 Ah. Alteration of the Hitachi screwdriver will be considered. Lithium batteries provide the device with a long service life.

Choose the rated voltage

First of all, you should decide on the choice of a voltage rating indicator for a lithium-based device. The choice should be made between the 3S-model (its voltage range is from 12.6 to 7.5 V) and the 4S-Li-Ion-battery (voltage range is from 16.8 to 10 V).

The advantages of the second option

The second option is more suitable, because the voltage in the battery drops quite quickly from maximum to minimum (from 16.8 to 14.8 V). For an electric motor, which, in fact, is a screwdriver, an excess of 2.8 V is not a critical mark.

The lowest voltage rating of the 3S-Li-Ion-modification. It is equal to 7.5 V, which is insufficient for the normal functioning of the electrical device. Having mounted four configurations, we will increase the electric capacity of the battery.

How to decide on the choice of lithium cells?

To select cells based on lithium, limiting factors should be identified. Currently, lithium devices are being manufactured with a permissible current load of 20-25 A.

Pulse current values ​​(short, up to 1-2 seconds) reach 30-35 A. The configuration of the battery will not be disturbed.

How many cells will fit in the case?

Collect 4S2P (four serial connections and two parallel) does not work. Converting a screwdriver to lithium 18650 batteries involves eight cells. How do they fit in four? Each cell will bear the maximum current load.

How to determine the maximum current in a screwdriver?

Converting a 12V screwdriver to lithium batteries involves connecting the device to a laboratory power supply with a maximum current of 30 A. The limiter regulator is set to the maximum value. Having created the voltage level of the power source close to the nominal indicator of the future battery, we begin to gently pull the trigger. The current consumed by a screwdriver rises to around 5 A. Now you should sharply pull the trigger. This will short circuit the supply circuit. The current will reach a power of 20-30 A. Perhaps its indicator would be much higher, but the power of the power source will not allow this to be fixed. This will be a short load current with a sharp pull on the trigger of a screwdriver. Any model of such a device will react similarly.

Next, clamp the tip of the screwdriver with a vise and observe to what value the current consumption increases during operation, when a ratchet works in the screwdriver. The current indicator in this case increases to 10-12 A.

So you can determine the magnitude of the load current. In this case, it will be equal to 5 A at idle and 30 A at a sharp start, and at maximum load it will be 12 A. The manufacturer should choose lithium cells, the rated indicator of the load current of which will be 10-20 A, and pulse. 25-30 A.

How to choose a controller?

So, the screwdriver is being converted to lithium batteries. Regular charging for the device is required. When choosing a controller, note that the device must meet two parameters:

  • rated operating voltage indicator;
  • rated operating current.

With the voltage, everything is very clear: if the battery is 11.1 V, then the controller will be with the same voltage.

The term "rated operating current" refers to the throughput protection of the board. Thus, the 4 A controller is designed for a 4 A current mark, and with an indicator of 8 A, an additional load is placed on it. In this case, the protective device will trip. All these technical data are stated in the passport of each controller modification. In this case, one modification may have a limit current of 30 A, and the other 50 A. And both of these devices will formally be suitable for operation. Also, when creating a lithium battery, there is a limitation in size. Therefore, you should purchase a controller that fits in the body of an old battery.

Disassembly and assembly

Converting a screwdriver to lithium batteries includes the following steps:

  • The old battery should be opened by unscrewing five screws.
  • Remove the Ni-Mh battery from the housing. It will be noticeable that the contact pad, which engages with the contact group of the screwdriver, is welded to the negative contact of one of the Ni-Mh cells. Welding points must be cut off using a tool with a DREMEL 4000 cutting stone mounted in it.
  • The wires are soldered to the contacts, the cross section of which is at least 2 mm 2 for power leads and 0.2 mm 2 for a thermistor. The contact pad is glued into the battery housing using hot melt adhesive.
  • According to the internal resistance index, four cells are selected on the meter. The value must be the same for all four devices.
  • Lithium cells are glued with hot melt so that they are located compactly in the housing.
  • Welding of cells is carried out on a resistance welding machine using a welding tape made of nickel (its cross-section should be 2X10 mm).

Installing the protection board

This step can show how lightweight the lithium battery design is. The weight of the Ni-Mh device was 536 g. The weight of the new lithium device is 199 g, which will be quite noticeable. We managed to win 337 g in weight. At the same time, an increase in energy capacity was observed.

The battery is mounted in a housing. The voids are filled with soft material from the packaging.

Connect to a screwdriver

  • A sharp pull on the trigger triggers the protection mechanism for current. But in fact, such a protective regime is unlikely to be needed when using the tool. If you do not specifically provoke protection, then the work of a screwdriver will be stable.
  • The tip should be clamped in a vice. Battery power freely triggers a ratchet, which limits the increase in the number of torsional revolutions.
  • The lithium screwdriver battery discharges at electronic load. The discharge current should be 5 A.
  • The battery is inserted into the standard memory. The charge current during measurement is 3 A, which is acceptable for lithium cells. For the LG INR18650HG2 configuration, the maximum charge current will be 4 A, which is indicated in the technical specification.

How long does it take to replace batteries?

Converting a screwdriver to lithium batteries will take about 2 hours. If all parameters are checked, then it will take 4 hours.

Everything can be done independently, without the help of another person. But contact welding and the choice of batteries without specialized equipment can not be done.

How else can I test the degree of charge other than the controller?

Converted screwdriver to lithium batteries. Regular charging, built into the case, is ideal. But the cost of the controller is quite high. The device will cost 30, which is equivalent to the cost of the battery itself.

To test the battery charge level of lithium on the go, without using a charger, you can use the special RC helicopter lipo battery AKKU portable voltage meter tester alarm 2-6S AOK indicator. The cost of the device is very low. It has a balancing and charging connector similar to the iMax6. The device is connected to the battery through an adapter. This voltage level monitor is very convenient. It can measure from two to six lithium cells connected in series, and also give a total indicator or voltage of each element separately with extreme accuracy.

How much will it cost to replace a Ni-Mh with a lithium device?

How much money would an alteration of a screwdriver for a lithium battery require?

The price of such a device consists of the cost of several components:

  • configuration of a 4S-battery based on lithium costs 2200 p ;
  • buying a controller for charging and discharging plus a balancer costs 1240 p.;
  • the cost of welding and assembly is 800 p.

It turns out that a self-made lithium battery costs 4240 p.

For comparison, we take a similar configuration from factory-made lithium. For example, a Makita 194065-3 device is designed for a screwdriver. It has similar parameters. The cost of such a device is 6500 p. It turns out that remaking a screwdriver on lithium batteries saves 2,300 p.

Alteration Screwdriver 18 V On Lithium

Converting a screwdriver to lithium batteries: instructions

Converting a screwdriver to lithium batteries makes sense. The advantage will be that they have a huge electron density. And therefore, by installing such a device in the case of a screwdriver, we can achieve an increase in the duration of the tool by a lot. The charging current for lithium batteries of the highest power, in particular for new versions, like oil sometimes reaches 1-2 C. It can be charged in 1 hour, in this case without overstating the manufacturer’s recommended specifications and without even spoiling the product quality.

What do lithium batteries look like?

Most of the lithium devices are enclosed in a prismatic case, but some models have a cylindrical shape. These batteries use coil electrodes, not separators. The body is made of aluminum in different steel. The positive pole goes to the housing cover.

In prismatic configurations, the electrodes are in the form of rectangular plates. I read part of the text. I also had a problem with ak from 18 screwdrivers. I stumbled upon a scheme in the 2006 radio magazine number 3. To ensure safety in the battery, a device is foreseen that acts as a regulator of all processes and does not open the electronic circuit in critical situations. The excessive sealing of the casing prevents the electrolyte from leaking out and oxygen does not seep inside, not moisture.

What precautions should be taken to prevent damage to the lithium battery?

  • Due to technology limitations, the charge indicator of lithium batteries does not exceed 4.25-4.35 V. The discharge should not reach the indicator 3.5.5-2.7. This condition is indicated in the technical data sheet for each specific model. If you overstate these values, you can disable the device. Special non-discharging charge controllers are used that maintain voltage on the lithium cell during normal operation. Alteration A screwdriver for a lithium battery with a controller will protect the device from a malfunction.
  • The voltage rating of lithium batteries is a multiple of 3.7 V (3.6 V). For Ni-Mh models > myth indicator is 1.2.7 V. This phenomenon is explainable. Model schemes for the 18th century. At 18 in, the charger circuit for a screwdriver involves the use of transistors of only a transition type. The rated voltage in lithium devices is stored in a separate cell. A 12 volt lithium battery will never be assembled. The rating will be equal to 11.1 V (three alternating cells), another 14.8 V (four alternating cells). In addition, the voltage indicator of the lithium cell changes during operation when working>> version charged at 4.25 V, and when <working discharge. by 3.5.5 V. The voltage indicator 3S (3 serial. three alternate connections) will change during the operation of the device from 12.6 V (4.2×3) to 7.5 V (3.5.5×3). For the 4S configuration, this indicator ranges from 16.8 to 10 V.
  • Alteration A screwdriver for 18650 lithium batteries (most products have this particular size) asks for differences in size with Ni-Mh cells. The diameter of the cell 18 650 is 18 mm, and the height is 65 mm. The fundamental condition is to calculate how many cells fit in the case. It should immediately be remembered that for a model with a power of 11.1 V, you need the number of cells that is a multiple of three. Converting a screwdriver to lithium batteries :. For a model with a power of 14.8 V. four. The controller should also fit non-patch wires.
  • The lithium-based battery charging device is different from the Ni-Mh modification.

The text of the article will consider how the rework screwdriver on lithium Li-Po batteries. Model schemes for the 18th century. At 18 in, the charger circuit for a screwdriver involves the use of transistors of only a transition type. The tool is equipped with a pair of Ni-Mh batteries with a voltage rating of 12 V and a capacity of 2.6 Ah. Will be considered alteration screwdriver Hitachi. Lithium batteries provide the device with a long service life.

Choose the rated voltage

Immediately you should correctly select the voltage rating indicator for the device based on lithium. The choice should be made between the 3S-model (its voltage spectrum is from 12.6 to 7.5 V) not 4S-Li-Ion-battery (voltage spectrum. From 16.8 to 10 V).

The advantages of the second option

The second option is more suitable, because the voltage in the battery drops quite rapidly from the highest to the lowest (from 16.8 to 14.8 V). For an electronic motor, which, in fact, is not a screwdriver, an excess of 4.8 V is not a critical mark.

The smallest voltage indicator of the 3S-Li-Ion-modification. It is equal to 7.5 V, which is missing for the production activity of an electronic device. Having mounted four configurations, we will increase the electric capacity of the battery.

How to decide on the choice of lithium cells?

Read the same

To select cells based on lithium, limiting factors should be identified. Currently, lithium devices are being manufactured with a permissible current load of 20-25 A.

Pulse current values ​​(short, up to 1-2 seconds) reach 30-35 A. The configuration of the battery will not be disturbed.

How many cells will fit in the case?

Collect 4S2P (four serial connections and two parallel) does not work. Alteration screwdriver 18650 lithium batteries suggest eight cells. I read part of the text. I also had a problem with ak from 18 screwdrivers. I stumbled upon a scheme in the 2006 radio magazine number 3. How do they fit in four? Each cell will bear the maximum current load.

Rework of 18 volt screwdriver on lithium. Almost free.

Alteration 18 volt shurik on lithium ion batteries (18650s) without controllers and balancers. Nearly

Converting an 18 volt screwdriver battery from Ni-Cd to Li-ion

Links to protection boards for lithium and another option fee is suitable for

How to determine the maximum current in a screwdriver?

Converting a 12V screwdriver to lithium batteries involves connecting the device to a laboratory power supply with a maximum current of 30 A. The article will discuss how the conversion of a screwdriver to li-po lithium batteries occurs. The limiter knob is set to the maximum value. Having created the voltage level of the power source close to the nominal indicator of the future battery, we begin to gently pull the trigger. The current consumed by a screwdriver rises to around 5 A. Now you should sharply pull the trigger. This will short circuit the supply circuit. The current will reach a power of 20-30 A. Converting a screwdriver to lithium batteries :. Perhaps his figure would be much higher, but the power of the power source will not allow this to be fixed. This will be a short load current with a sharp pull on the trigger of a screwdriver. Any model of such a device will react similarly.

Next, clamp the tip of the screwdriver with a vise and observe to what value the current consumption increases during operation, when a ratchet works in the screwdriver. The current indicator in this case increases to 10-12 A.

So you can determine the magnitude of the load current. In this case, it will be equal to 5 A at idle and 30 A at a sharp start, and at maximum load it will be 12 A. The manufacturer should choose lithium cells, the rated indicator of the load current of which will be 10-20 A, and pulse. 25-30 A.

How to choose a controller?

So, the screwdriver is being converted to lithium batteries. Regular charging for the device is required. When choosing a controller, note that the device must meet two parameters:

  • rated operating voltage indicator;
  • rated operating current.

With the voltage, everything is very clear: if the battery is 11.1 V, then the controller will be with the same voltage.

The term "rated operating current" refers to the throughput protection of the board. Thus, the 4 A controller is designed for a 4 A current mark, and with an indicator of 8 A, an additional load is placed on it. In this case, the protective device will trip. All these technical data are stated in the passport of each controller modification. In this case, one modification may have a limit current of 30 A, and the other 50 A. And both of these devices will formally be suitable for operation. Also, when creating a lithium battery, there is a limitation in size. Therefore, you should purchase a controller that fits in the body of an old battery.

Disassembly and assembly

Converting a screwdriver to lithium batteries includes the following steps:

  • The old battery should be opened by unscrewing five screws.
  • Remove the Ni-Mh battery from the housing. It will be noticeable that the contact pad, which engages with the contact group of the screwdriver, is welded to the negative contact of one of the Ni-Mh cells. The article will examine how the alteration of a screwdriver on li-po lithium batteries occurs. Welding points must be cut off using a tool with a DREMEL 4000 cutting stone mounted in it.
  • The wires are soldered to the contacts, the cross section of which is at least 2 mm 2 for power leads and 0.2 mm 2 for a thermistor. The contact pad is glued into the battery housing using hot melt adhesive.
  • According to the internal resistance index, four cells are selected on the meter. The value must be the same for all four devices.
  • Lithium cells are glued with hot melt so that they are located compactly in the housing.
  • Welding of cells is carried out on a resistance welding machine using a welding tape made of nickel (its cross-section should be 2X10 mm).

Installing the protection board

Read the same

This step can show how lightweight the lithium battery design is. The weight of the Ni-Mh device was 536 g. The weight of the new lithium device is 199 g, which will be quite noticeable. We managed to win 337 g in weight. At the same time, an increase in energy capacity was observed.

The battery is mounted in a housing. The voids are filled with soft material from the packaging.

Connect to a screwdriver

  • A sharp pull on the trigger triggers the protection mechanism for current. But in fact, such a protective regime is unlikely to be needed when using the tool. If you do not specifically provoke protection, then the work of a screwdriver will be stable.
  • The tip should be clamped in a vice. Battery power freely triggers a ratchet, which limits the increase in the number of torsional revolutions.
  • The lithium screwdriver battery discharges at electronic load. The discharge current should be 5 A.
  • The battery is inserted into the standard memory. Converting a screwdriver to lithium batteries :. The charge current during measurement is 3 A, which is acceptable for lithium cells. For the LG INR18650HG2 configuration, the maximum charge current will be 4 A, which is indicated in the technical specification.

How long does it take to replace batteries?

Alteration screwdriver on lithium batteries will take about 2 hours. If all parameters are checked, then it will take 4 hours.

Everything can be done independently, without the help of another person. Converting a screwdriver to lithium batteries :. But contact welding and the choice of batteries without specialized equipment can not be done.

How else can I test the degree of charge other than the controller?

Implemented by alteration screwdriver for lithium batteries. Regular charging, built into the case, is ideal. But the cost of the controller is quite high. The device will cost 30, which is equivalent to the cost of the battery itself.

To test the battery charge level of lithium on the go, without using a charger, you can use the special RC helicopter lipo battery AKKU portable voltage meter tester alarm 2-6S AOK indicator. The cost of the device is very low. It has a balancing and charging connector similar to the iMax6. The device is connected to the battery through an adapter. This voltage level monitor is very convenient. How to determine the maximum current in a screwdriver? Converting a 12v screwdriver to lithium batteries involves connecting the device to a laboratory power source It can measure from two to six lithium cells connected in series, and also give a total indicator or voltage of each element separately with extreme accuracy.

How much will it cost to replace a Ni-Mh with a lithium device?

How much money would an alteration of a screwdriver for a lithium battery require?

The price of such a device consists of the cost of several components:

  • configuration of a 4S-battery based on lithium costs 2200 p ;
  • buying a controller for charging and discharging plus a balancer costs 1240 p.;
  • the cost of welding and assembly is 800 p.

It turns out that a self-made lithium battery costs 4240 p.

For comparison, we take a similar configuration from factory-made lithium. For example, a Makita 194065-3 device is designed for a screwdriver. It has similar parameters. The cost of such a device is 6500 p. It turns out that remaking a screwdriver on lithium batteries saves 2,300 p.