Alteration Of A Screwdriver For 12v Lithium Batteries

Conversion of the “Hitachi” 12 V screwdriver to 18640 lithium batteries

Peculiarities of reworking the 12 V Hitachi screwdriver for lithium batteries. The very compact battery compartment is designed for finger cells. Therefore, you should prepare a place for 18650 cells. It is necessary to cut one side into the partitions in order to tightly place 1 element.

You need to get a gumboil, a flat metal connecting tape, hot glue. It is necessary to install lithium batteries in a screwdriver during rework through a protective controller. It should service 3 18650 cells, 3.7V and rated for 20-30 amps.

Remove the old battery from the socket, carefully disconnect the contacts in the assembly with the temperature sensor and the power indicator. Clean up and sign contacts. They should be brought out in one direction, connected with solder to the leads from thick wires and filled with hot melt glue on the assembly.

Alteration Of A Screwdriver For 12v Lithium Batteries

Assemble a power source with one of the 3 cell controllers. Build a serial circuit of 3 Li-ion cells. Connect the controller. The conversion of the 12-volt lithium battery is completed when the structure is installed in the unit, secured, and the charging indicator lights up. After fully charging, the measurements show 12.17 volts in the external network. But this is enough for trouble-free long-term operation of the device.

Accumulators and batteries

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Conversion of a screwdriver to lithium batteries 18650 14 V

When converting screwdrivers of different power and flashlights from Ni-Cd to Li-ion, batteries of the form factor 18650 are more often used. They easily fit into a container or a nest, since instead of two or three relatives, one lithium is installed. Alteration of the screwdriver battery should be carried out taking into account the peculiarities of lithium 18650 batteries.

This kind of energy source does not tolerate deep discharge and unnecessary charge. Hence, it is necessary to use voltage control boards. Since each battery has its own character, their charge is adjusted by a balancer. The point of reworking a screwdriver with a voltage of 14.4 V lies in the creation of a device with the introduction of lithium batteries to facilitate the hand tool and increase its performance. Lithium 18650 batteries are most suitable for THESE purposes.

When selecting accessories, it should be taken into account that the starting current of the screwdriver is high, you must select the Corresponding BMS for the required number of cans and at least 30 A.

Lithium-ion cans in the amount of 4 pcs.
4-cell li-ion battery controller, CF-4S30A-A works well. It has a built-in balancer that controls the charge of each element.
Hot glue, flux for soldering TAGS, solder.
Heat-resistant adhesive tape;
Jumpers or thick insulated wire with a cross-section of at least 0.75 squares, cut for bridges.

The procedure for reworking a screwdriver for 18650:

Disassemble the case and remove a bundle of 12 Ni-Cd cells from the container.
Remove the garland, leave the connector with leads “” and “-“. Instead of a temperature sensor, a thermocouple from the controller will be installed.
Solder the assembly, Considering that you cannot use acid, only neutral flux and pure solder. During the connection period, the lid must not be heated. Work pointwise.
Connect balancing points to the controller according to the diagram. The board has connectors.
Connect assembly with plus and minus pins.
Check the functionality of the circuit. If everything works, Assemble the battery, place the controller in the socket, secure with a sealant.

If the charger is NOT universal, additional alteration will be required. Screwdrivers for 12 V with a universal charger are assembled in the same way, but a protective connection circuit 3×18650 3.7 V for lithium batteries is used. In the same way, a screwdriver is being reworked with the introduction of a set of 18650 batteries in the amount of 2 parts.

The meaning and procedure for converting screwdrivers to lithium batteries

Why do nickel-cadmium batteries fail quickly? Each garland of cans connected in series is special. The chemical process is individual, the charge in closed systems is different. In the event of a malfunction in one bank, the design does not provide the required voltage. The control system and charge balancing in SEPARATE components is not provided.

Each Ni-Cd bank provides 1.2V, and the Li-ion 18650 provides 3.6V.
Lithium battery capacity is 2 times that of nickel-cadmium battery, similar size.
An overheated li-ion battery threatens an explosion and fire, therefore, the installation of monitoring the uniformity of the charge in the banks is mandatory. BMS is NOT installed in nickel-cadmium batteries. the manufacturer is NOT interested.
Lithium cells have a memory effect, unlike Ni-Cd, they can be charged at any time and within an hour.
The screwdriver becomes much easier after converting the battery to li-ion, with the introduction of 18650 cells.

There are only two obstacles to converting a screwdriver for lithium batteries. it is impossible to work with it at minus. The capacity of cans decreases, starting from a decrease already from 10 0 C. Lithium batteries are expensive.

Knowing what input voltage is required for the screwdriver, the charger is reworked, taking into account the placement of the lithium battery cans and control elements in the factory container. You can also do with a flashlight by upgrading the socket for a block of 18650 cells.

Let’s say you need to rework a 12 V screwdriver using Ni-Cd cans on li-ion. If you use 3 banks, the output voltage is not enough 3.6 x 3 = 10.8 V. With 4 components, the power of the apparatus will be higher than 3.6 x 4 = 14.4 V. In this case, the instrument will become 182 g lighter, somewhat its power will increase, capacity. solid pluses. But when dismantling, you must leave the terminals and the native thermal sensor.

Conversion of the Makita screwdriver to the lithium battery

There is a “Makita” screwdriver with a 1.3 A / h battery and a voltage of 9.6 V. To change the power source to a lithium-ion one, you will need 3 18650 components. The alteration will give the old tool new possibilities: it will increase the operating time on a single charge. will add power as the operating voltage rises to 10.8V.

The design will require the use of a BMS, a control controller that maintains the lithium cell operating mode within operating limits. With this breaker, each cell will be charged evenly without exceeding 4.2V, lower voltage 2.7V. Built-in balancer is used here.

Controller parameters Should accompany the operation of the tool with an increase in the operating current to 10-20 A. The Sony VTC4 30 A board, designed for a capacity of 2100 A / h, will be able to ensure operation without shutdown.Of 20 amperes, Sanyo UR18650NSX accepting energies of 2600 / h is suitable. for 3 elements, which is marked in the 3S classification. In this case, the board must have 2 contacts, plus and minus. If the conclusions are designated with the letters “P”, “P”, “C-“, they are intended for later models of screwdrivers.

Step-by-step instructions for converting a Makita screwdriver to lithium batteries looks like this.

You can disassemble the battery with glue if you tap the junction with a soft-headed hammer while weighing. Direction of impact downwards, in Butt on the lower part of the body.
Take here of the old assembly only the contact plates, carefully disconnecting them from the battery. Leave the sensor and breaker.
Solder 3 elements in series using TAGS flux and insulated jumpers. The wire cross section must be greater than 0.75 mm2.
Assemble the circuit with the controller, and connect the power supply to the contact connectors with 1.5 square wires.
Check the operation of the circuit and assemble the case, put it back on the glue.

In a screwdriver with an old DC9710 charger, after charging the 18650 lithium battery, the red LED on the panel will turn off. The built-in controller monitors the charge level.

The Makita DC1414 T charger is used to charge 7.2-14.4 V power sources. While charging, the red light is on. But when charging a lithium battery, its voltage does NOT fit into the standards of salt products, and after 12 V, the charger will flash red and green. But the required charging is already there. The screwdriver is ready to work.

Converting a screwdriver to lithium batteries 18650

Every craftsman is faced with the problem of reduced tool performance, or complete failure due to the battery. Manufacturers use nickel-cadmium batteries in 12-volt, 14-volt, 18-volt screwdrivers. The sequential assembly of several elements creates the desired voltage. Replacing nickel-cadmium batteries with lithium batteries extends battery life by making the design lighter. Mandatory BMS board installation adds reliability. Therefore, the conversion of a screwdriver to lithium batteries, mainly to the 18650 form factor, is justified.

Conversion of the Interskol screwdriver for lithium 18650 batteries

Sooner or later, the nickel-cadmium assembly of 15 cans fails. One or two elements are lazy, and it is no longer possible to get the output voltage. Modern DSh “Interskol” on lithium batteries serve much better. Alteration of a screwdriver for 18 volt lithium batteries mastered by craftsmen.

It is necessary to purchase a protection board for 5S, 3.7 V and 40-50 A. You will need a balancing board and the energy sources themselves. 5 lithium 18650 batteries, you can leave them with the factory thermistors by extending the wires. During installation, create a contact pad, insert the assembly, check the operability, secure. Features of assembly wizard tips are given in detail in. See here for complete information on reworking an 18-volt lithium screwdriver

Difference from nickel cadmium batteries

Historically, the first truly mass-produced rechargeable batteries for handheld power tools were nickel-cadmium batteries. At a low price, they are quite capable of large loads and have a satisfactory electrical capacity with reasonable dimensions and weight. Batteries of this type are still widespread today, especially in the low-cost handheld appliance sector.

The main difference between lithium batteries and nickel-cadmium batteries is low weight with high electrical capacity and very good load capacity.

In addition, a very important difference between lithium batteries is the significantly shorter charging time. This battery can be charged in a couple of hours. But the full charge cycle of nickel-cadmium batteries takes at least twelve hours.

There is another peculiarity associated with this: while lithium batteries can easily tolerate both storage and operation in an incompletely charged state, nickel-cadmium batteries have an extremely unpleasant “memory effect”. In practice, this means that in order to extend the service life, as well as to prevent a rapid loss of capacity, it is advisable to use nickel-cadmium batteries until they are completely discharged. After that, be sure to charge to full capacity, which takes a considerable time.

Lithium batteries do not have this disadvantage.

How to charge properly?

Lithium batteries are quite picky about charger specifications. Such batteries can be charged fairly quickly with a significant current, but excessive charging current leads to severe heating and fire hazard.

It should also be borne in mind that when cells are connected in series in a battery, lithium sources are very prone to uneven charging of SEPARATE cells. This leads to the fact that it is not possible to charge the battery to its full capacity, and the cell, which regularly works in undercharged mode, simply wears out faster. Therefore, chargers are usually built according to the “charge balancer” scheme.

Fortunately, all modern factory-made lithium batteries (except for outright fakes) have built-in protection and balancing circuits. However, the charger for such batteries must be specialized.

Advantages and disadvantages

The main advantage of lithium batteries is their high electrical capacity. This allows you to create a lightweight and compact hand tool. On the other hand, if the user is ready to work with a heavier device, he will receive a very powerful battery that allows you to work with a screwdriver for a long time.
Another advantage is the ability to quickly charge lithium batteries with energy. A typical full charge time is approximately two hours, and some batteries can be charged in half an hour with a special charger! This advantage can be an exceptional reason for equipping a screwdriver with a lithium battery.

There are some specific disadvantages in lithium batteries.

The most noticeable is the significant drop in practical capacity when working in cold weather. At negative temperatures, tools equipped with lithium batteries have to be warmed up from time to time, while the electrical capacity is fully restored.
The second noticeable disadvantage is NOT too long service life. Despite the assurances of the manufacturers, the best samples, with the most careful operation, can withstand no more than three to five years. Within a year after the purchase, a lithium battery of any common brand, with the most careful use, can lose up to a third of its capacity. After two years, hardly half of the original capacity will remain. Average life of normal operation is two to three years.
And another notable drawback: the price of lithium batteries is much higher than the cost of all nickel-cadmium batteries still widely used in hand-held power tools.

Features:

The design of a lithium rechargeable battery is NOT too different from a battery based on a different chemistry. But the fundamental feature is the use of anhydrous electrolyte, which prevents the release of free hydrogen during operation. This was a significant disadvantage of the batteries of the previous designs and led to a high probability of fire.

The anode is made of a film of cobalt oxide deposited on an aluminum base-current collector. The cathode is the electrolyte itself, containing lithium salts in liquid form. The electrolyte impregnates a porous mass of electrically conductive chemically neutral material. Loose graphite or coke is suitable for it. Current collection is carried out from a copper plate superimposed on the back of the cathode.

For normal battery operation, the porous cathode needs to be pressed tightly enough to the anode. Therefore, in the design of lithium batteries, there is always a spring that compresses the “sandwich” from the anode, cathode and negative current collector. The ingress of ambient air can upset the carefully balanced chemical balance. And the ingress of moisture and does threaten the danger of fire and even explosion. Therefore, the finished battery cell must be carefully sealed.

A flat battery is simpler in design. All other things being equal, a flat lithium battery will be lighter, much more compact, and provide significant current (that is, more power). But it is necessary to design a device with flat-shaped lithium batteries, which means that the battery will have a narrow, specialized application. Such batteries are more expensive than their counterparts.

To make the sales market wider, manufacturers produce battery cells with universal shapes and standard sizes.

Among lithium batteries today, the 18650 version actually dominates. Such batteries have a look similar to the cylindrical finger-type batteries familiar in everyday life. But the 18650 standard specifically provides for somewhat larger dimensions. This avoids confusion and prevents such a power supply unit from being mistakenly replaced in place of a conventional saline battery. But this would be very dangerous, since the lithium battery has two and a half times the standard voltage (3.6 volts versus 1.5 volts for a salt battery).

For an electric screwdriver, lithium cells are sequentially collected into a battery. This allows the voltage to the motor to be increased to provide the power and torque the tool needs.

The rechargeable battery necessarily contains in its design temperature sensors and a specialized electronic device. a controller.

This circuit:

Monitors the uniformity of the charge of INDIVIDUAL elements;
Controls the charge current;
DOES NOT over-discharge cells;
Prevents battery overheating.

Batteries of the described type are called ionic. There are also lithium-polymer cells, this is a modification of lithium-ion. Their design is fundamentally different only in the material and design of the electrolyte.

Features, advantages and disadvantages of lithium batteries for screwdriver

If a hand-held power tool powered by a household power supply is tied to an outlet with a wire, Restrict the movements of the person holding the device in his hands, then the cordless counterparts of the units “on a leash” provide much more freedom of action in work. A battery is essential when it comes to using screwdrivers.

Depending on the type of battery used, they can be conditionally divided into two groups. with nickel and lithium batteries, and the features of the latter make this power tool the most interesting for the user.

How to remake and assemble?

Often, the master already has an old cordless screwdriver, which suits him completely. But the device is equipped with outdated nickel-cadmium batteries. Since the battery will still have to be changed, there is a desire to replace the old battery with something newer. This will not only provide more comfortable work, but also eliminate the need to look for older batteries on the market.

The simplest thing that comes to mind is to assemble a power supply from an electronic transformer in an old battery case. Now you can use the screwdriver by connecting it to the household power supply.

14.4 volt models can be connected to a car battery. Having assembled an extension adapter with terminals or a cigarette lighter plug from the body of an old battery, you get an indispensable device for a garage or work “in the field”.

If we are converting an old battery to a cast one, we can take into account that 18650 lithium cells are extremely widespread on the market. Thus, we can make screwdriver batteries based on readily available parts. over, the prevalence of the 18650 standard allows you to choose batteries from any manufacturer.

Opening the case of the old battery and removing the old filling from it will not be difficult. It is important not to forget Mark on the body the contact to which the “plus” of the old battery assembly was previously connected.

Depending on the voltage for which the old battery was designed, it is necessary to select the number of lithium cells connected in series. The standard voltage of a lithium cell is exactly three times that of a nickel cell (3.6 V instead of 1.2 V). Thus, each “cast” replaces three series-connected “nickels”.

By providing for the design of the battery, in which three lithium cells are connected one after the other, it is possible to obtain a battery with a voltage of 10.8 volts. Among nickel batteries, these are found, but not often. When four lithium cells are connected to a garland, we already get 14.4 volts. This will allow replacing the nickel battery with both 12 volts and 14.4 volts. these are very common standards for nickel-cadmium and nickel-metal hydride batteries. It all depends on the specific model of the screwdriver.

After it was possible to determine the number of successive stages, it will probably become clear that there is still free space in the old building. This will make it possible to connect two cells in parallel in each stage, which will double the battery capacity. To connect lithium batteries to each other in production, a nickel strip is used. Sections of tape are connected to each other and to lithium elements by resistance welding. But in everyday life, it is quite acceptable soldering.

Soldering lithium cells should be done with great care. The joint must be thoroughly cleaned beforehand and a good flux must be applied. Tinning is done very quickly, with a well-heated soldering iron of sufficiently high power.

The soldering itself is performed by fast and confident heating of the place where the wire is connected to the lithium cell. To avoid dangerous overheating of the element, the soldering time should not exceed three to five seconds.

It is good that now there are ready-made electronic control and balancing modules on sale at fairly low prices. It is enough to choose the solution that suits your particular case. Basically, such controllers differ among themselves by the number of series-connected “steps”, the voltage between which is subject to equalization (balancing). In addition, they differ in their permissible load current and temperature control method.

In any case, it is no longer possible to charge a homemade lithium battery with an old nickel battery charger. They have fundamentally different charging algorithms and control voltages. You will need a dedicated charger.

How to choose?

When it comes to choosing a battery for a screwdriver, the task comes down to the selection of the electrical device itself, complete with which there will be a battery of a specific model.

The rating of inexpensive cordless screwdrivers this season looks like this:

Makita HP331DZ, 10.8 volts, 1.5 Ah, cast;
Bosch PSR 1080 LI, 10.8 volts, 1.5 Ah, cast;
Bort BAB-12-P, 12 volt, 1.3 Ah, nickel;

“Interskol DA-12ER-01”, 12 volts 1.3 Ah, nickel;
Kolner KCD 12M, 12 volt, 1.3 Ah, nickel.

The best professional models are:

Makita DHP481RTE, 18 V, 5 Ah, cast;
Hitachi DS14DSAL, 14.4 volts, 1.5 Ah, cast;
Metabo BS 18 LTX Impuls 201, 18 volt, 4 Ah, cast;
Bosch GSR 18 V-EC 2016, 18 volts, 4 Ah, cast;
Dewalt DCD780M2, 18 V 1.5 Ah, cast.

The best reliable cordless screwdrivers:

Bosch GSR 1440, 14.4 volts, 1.5 Ah, cast;
Hitachi DS18DFL 18V 1.5Ah Cast
Dewalt DCD790D2, 18 V, 2 Ah, cast.

This voltage is considered the industry professional standard for lithium batteries. Since a professional tool is designed for long-term active work, and also implies an additional level of comfort, a significant part of the produced 18-volt screwdriver batteries are fully compatible with each other, and sometimes even interchangeable between tools from different manufacturers.

In addition, 10.8 volt and 14.4 volt standards are widely used. The first option is found only among the most inexpensive models. The second is traditionally “middle peasant” and can be found both among professional models of screwdrivers and in models of the middle (intermediate) class.

But the designations of 220 volts in the characteristics of the best models cannot be seen, since this indicates that the screwdriver is connected to the household power outlet by the manual.

How to store?

The great thing about lithium batteries is that they are NOT overly demanding on storage conditions. They can be stored whether charged or discharged at almost any reasonable temperature. If only it was not too cold. Temperatures below 25 degrees Celsius are fatal for most types of lithium batteries. Well, above 65 degrees of heat is also Better not overheating.

However, when storing lithium batteries, be sure to take into account the very high probability of fire.

Proper storage conditions are when the battery is at least 50% charged and the room temperature is between 0 and 40 degrees. At the same time, it is advisable to save batteries from moisture, including in the form of drip (dew).

Which battery is better for a screwdriver, you will find out in the following.

Conversion of the Makita screwdriver to the lithium battery

Step-by-step instructions for converting a Makita screwdriver to lithium batteries looks like this.

You can disassemble the battery with glue if you tap the junction with a soft-headed hammer while weighing. Direction of impact downwards, in Butt on the lower part of the body.
Take here of the old assembly only the contact plates, carefully disconnecting them from the battery. Leave the sensor and breaker.
Solder 3 elements in series using TAGS flux and insulated jumpers. The wire cross section must be greater than 0.75 mm2.
Assemble the circuit with the controller, and connect the power supply to the contact connectors with 1.5 square wires.
Check the operation of the circuit and assemble the case, put it back on the glue.

In a screwdriver with an old DC9710 charger, after charging the 18650 lithium battery, the red LED on the panel will turn off. The built-in controller monitors the charge level.

Conversion of the “Hitachi” 12 V screwdriver to 18640 lithium batteries

Convert a screwdriver to a 12 volt lithium battery

The inevitable has come. the batteries in my old Hitachi DS 12DVF3 are completely dead. They have become disgustingly holding a charge for a very long time, but the available capacity was enough for small household needs, so I never thought about solving this problem. By the time I needed to drill a hole in the stainless steel kitchen sink, which took me forty minutes! One hole! It was not possible to swing one battery at all, while the other did not work, twists twenty seconds, charges about ten minutes. It was then that I realized that it was time to give a new life to my favorite instrument.
It is clear that first it was necessary to get acquainted with the theory a little in order to understand what I have to do in general. Of course, this topic is not at all new, and everyone who is not lazy is engaged in the translation of screwdrivers into cast ones. But everyone does it in their own way, depending on their education, the amount of flax and the concept of beauty. I needed everything to be done absolutely correctly from the technical point of view, so that it did not look scary from the outside and that the batteries could be conveniently used. I read and reviewed a huge amount of material, I took as a basis from AlexGyver.

Here you need to carefully break off the upper contact pad, it will be needed later. You will also need nickel jumpers to solder the second block to the battery, so I move this stuff aside for now. Next, I try on new components so that the concepts of the front of the upcoming work.

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The meaning and procedure for converting screwdrivers to lithium batteries

Each Ni-Cd bank provides 1.2V, and the Li-ion 18650 provides 3.6V.
Lithium battery capacity is 2 times that of nickel-cadmium battery, similar size.
An overheated li-ion battery threatens an explosion and fire, therefore, the installation of monitoring the uniformity of the charge in the banks is mandatory. BMS is NOT installed in nickel-cadmium batteries. the manufacturer is NOT interested.
Lithium cells have a memory effect, unlike Ni-Cd, they can be charged at any time and within an hour.
The screwdriver becomes much easier after converting the battery to li-ion, with the introduction of 18650 cells.

There are only two obstacles to converting a screwdriver for lithium batteries. it is impossible to work with it at minus. The capacity of cans decreases, starting from a decrease already from 10 0 C. Lithium batteries are expensive.

Let’s say you need to rework a 12 V screwdriver using Ni-Cd cans on li-ion. If you use 3 banks, the output voltage is not enough 3.6 x 3 = 10.8 V. With 4 components, the power of the apparatus will be higher than 3.6 x 4 = 14.4 V. In this case, the instrument will become 182 g lighter, somewhat its power will increase, capacity. solid pluses. But when dismantling, you must leave the terminals and the native thermal sensor.

Conversion of a screwdriver to lithium batteries 18650 14 V

Lithium-ion cans in the amount of 4 pcs.
4-cell li-ion battery controller, CF-4S30A-A works well. It has a built-in balancer that controls the charge of each element.
Hot glue, flux for soldering TAGS, solder.
Heat-resistant adhesive tape;
Jumpers or thick insulated wire with a cross-section of at least 0.75 squares, cut for bridges.

The procedure for reworking a screwdriver for 18650:

Disassemble the case and remove a bundle of 12 Ni-Cd cells from the container.
Remove the garland, leave the connector with leads “” and “-“. Instead of a temperature sensor, a thermocouple from the controller will be installed.
Solder the assembly, Considering that you cannot use acid, only neutral flux and pure solder. During the connection period, the lid must not be heated. Work pointwise.
Connect balancing points to the controller according to the diagram. The board has connectors.
Connect assembly with plus and minus pins.
Check the functionality of the circuit. If everything works, Assemble the battery, place the controller in the socket, secure with a sealant.

If the charger is NOT universal, additional alteration will be required. Screwdrivers for 12 V with a universal charger are assembled in the same way, but a protective connection circuit 3×18650 3.7 V for lithium batteries is used. In the same way, a screwdriver is being reworked with the introduction of a set of 18650 batteries in the amount of 2 parts.

Conversion of the Interskol screwdriver for lithium 18650 batteries

For rework according to my version, we need:

– screwdriver Interskol Da-12ER-02)))
– soldering iron from 60W because Less powerful you DO NOT solder
– multimeter (tester)
– “Soldering acid”. There are many variations of them, we take with a brush

You can use a ready-made battery with an existing charger, but:

– there are complaints that the case will be very hot, which many fear. But the design of the charger uses a transformer and heating is normal for it. In my experiments at a current of 1A, he warmed up to 60C. The design does not provide for a current limiting system so that the current in the system can be several times higher and the heating is higher. At the same time, now we need more time to charge the batteries.
– in the design of the charger there is a system for limiting the charging time and it is one time. THOSE. We will have to juggle the battery to fully charge it.
– It will be hard to use the native charger if we decide to use 6 parts of the 18650 because The maximum current provided by the manufacturer’s statement must be 1.8A. THOSE. Prolonged use at currents above this value may lead to unknown consequences. For 3 parts with a capacity of 3000mAh and a recommended charge current of 0.5C.1C (1.5A. 3A), we fit into the charger’s parameters. For 6 cells, we need a charge current twice as much. And yes, as I said before, the charger has charge current limiting circuits i.e. In a certain period of time, we will charge our batteries at the aisles of the charger’s capabilities, which is tolerable for 3x, but not for 6 cells.

In principle, these are the main nuances of using a native charger.

Conversion of a screwdriver to 12V lithium batteries

This article covers:

What we have: the old Interskol Da-12ER-02 screwdriver quite vigorously working, but with dead batteries.

Our goal: to replace old Ni-Cd batteries with new li-ion

Precautions:

– when working with batteries, one must be extremely careful not to short-circuit x, at the moment of short-circuit at the point of contact, huge currents arise, which can lead to burns, eye damage, explosion and fires. As well as the exit from standing all the components.
– when working with acid, you must be extremely careful because It can get in the eyes, skin, etc. The consequences can be very sad.
– perform work only on disconnected equipment from the 220V power supply. It should also be borne in mind that capacitors are used in power circuits, which accumulate charge and when you disconnect the device from the network, This does not mean that the board is de-energized.

Battery:

Lithium 18650 batteries, for example we take batteries with tails. We need high current batteries.
Balance protection board 3S 40A 12.6V 40A lithium battery protection board
The wires are short, but thick with a cross section of 1.5
Double-sided tape
Thick wide Relatively soft pad 1.5-2 cm

Foreword

You can use 6 pcs. 18650, which will double our battery capacity, but will require a higher charge current, which will require abandoning the original power supply without alterations, and our charging will last oooooooooo long.

I want to draw your attention and this is very important, the batteries in the photo are not suitable for our task, this is my jamb, I did not think I bought it. Use only high amperage batteries. But Comrade K. I didn’t have options, I did on them.

Why do we need high-amperage batteries. lithium batteries are designed to be used in certain conditions of discharge charge, then what is allowed in the photo, cut them with currents of 2C, i.e. In this case, it is about 6 A. The screwdriver at the moment of start consumes a current from 15A to 25A and at a constant load of about 10A. As we can see, we have exceeded the manufacturer’s requirements. High-amperage batteries are designed for higher discharge currents from 10A, which guarantees us a longer service life, as well as fewer surprises in the future from improper use. Read in such batteries: read

Board with protection and balancing. will allow us to operate lithium batteries within the limits recommended by manufacturers. It will protect our batteries from deep discharge, as well as from overcharge, which is very critical for lithium batteries and violation of this point will lead to very rapid degradation of the battery, i.e. Loss of its capacity. Also, this board has a balancing circuit, which is designed to equalize the charge on each battery cell. Our batteries have a serial connection, which during operation will lead to their uneven charge read, which will lead to see paragraph 1, but this board will eliminate this effect. The presented board, upgraded at the request of workers and self-healing when the protection is triggered.

Charger (no need to remodel):

– buck DC-DC voltage converter (XL4015). Read the article about THESE converters
– breadboard, for example. We need a plump board.
– 4 diodes from 100V 3A or a ready-made diode bridge, I used to watch. Or it will be taken from the original charging board.
– capacitor from 470mkf 35V. Or it will be taken from the original charging board.
– two LEDs of different color 5mm.
– hot melt
– wires of various lengths and cross-sections.
– drills 2mm

Assembly:

We use the batteries with already welded ponytails. First of all, we remove the protection from the Khvostikov, then we need to ERASE the ends. RUNNING without using acid (carefully) you will not get it so that we take acid, a soldering iron and solder and tinker. We trick from both ends. Apply the acid in a thin layer, this is quite enough, otherwise you will get splashes in different directions.

If you bought acid without a brush, then you can pour it into a tube of nail polish, or you can use a disposable syringe, where you squeeze out a drop and immediately pull it back in, leaving a thin film. We also need to RUN the advantages of the first two batteries, in these places we will connect the batteries to each other.

After you have all tinned, we solder the batteries in series, see Fig. On one of the batteries, the tab is turned in the opposite direction. We also make soldering with a powerful soldering iron, simply by attaching a tongue and pressing it with a soldering iron tip. This is what we should get.

Now we fix everything with electrical tape or it can be done in advance before soldering. Glue double-sided tape to fix the board.

Let’s start soldering the batteries to the board.

Result:

We disassemble the native battery. We take out the old batteries (Caution).

Bite off the black piece and solder. We need thick wires because We will have current for 25A periods or more. That with thin wires can lead to their fire, as well as we will have a loss in power. Put the batteries aside carefully.

Now we need to find a thick, wide soft pad 1.5-2 cm. I tore it from the packaging of a certain gadget. Cut to the size of the case and put it on the bottom, glue the double-sided tape and glue the batteries. We fix that black thing, the protruding end should be of such length that it rested against our batteries and allowed the case to be closed with a certain tension. DO NOT reverse polarity!

In this case, the brown wire is minus, and the black wire is plus. Brown is an order of magnitude thicker than black.

Cutting the wires, making them as short as possible, so as NOT to lose current at losses, but we must take into account that we still need to be soldered to the board. We solder and assemble the case, the battery is ready.

Conversion of a screwdriver to lithium batteries. Battery preparation and assembly

Often there are cases when a high-quality screwdriver stops performing its functions due to a weak battery. It is a pity to throw out such a tool, it is better to rework the screwdriver battery. Nickel batteries are commonly found in low-cost equipment due to their poor performance.

Advantages of injection molded batteries:

Good current efficiency;
The power of the screwdrivers does not decrease when the battery is discharged;
The product is slowly discharging;
Charging time is 1-1.5 hours;
The battery can be recharged without damage to the volume.

Injection-molded batteries have a convenient “can” shape with a diameter of 18 mm and a length of 65 mm. To convert the screwdriver to a high-quality battery, you should purchase high-current cans.

To alter a screwdriver battery, you need to connect the molded batteries. A special battery compartment is prepared for this. You can also try soldering the devices, but this will require a weak soldering iron, since such products do NOT tolerate overheating. Experienced craftsmen use an accurate quarrel to connect injection molded batteries with their own hands.

It is important that all banks have the same capacity, otherwise a battery with a lower rating will fail faster. To secure the system, it is recommended to include board protection in the injection battery circuit.

Alteration sequence

To transfer the screwdriver to a molded battery, you need to disassemble the battery. It is recommended to leave the terminals from nickel devices. Any excess plastic inside the case should be removed. If there is not enough space, then the special compartment will have to be abandoned, and the circuit of the injection battery is connected by soldering. The board is glued to the top of the batteries using double-sided tape.

A thick power cable can be used as the power wire to connect the terminal block. Then a hole is made in the case to install a charging socket. The block with terminals is connected in parallel to the molding battery with your own hands with the output from the protection module. The wires are soldered vertically to the protection board.

It is important to fix the block with the terminals in order to prevent it from slipping (you can insert a regular bamboo skewer). Then the structure is assembled, the bolts are screwed in.

It remains to check the correctness of the conversion of the screwdriver for injection-molded batteries in practice. For this, the battery is connected to the tool and several screws are screwed.

Then the battery is fixed to the screwdriver. If there is only one battery, then it can be safely bolted. When it is possible to change the device, then you can use ordinary chamber rubber bands.

Sources:

http://stroy-podskazka.ru/shurupovert/litievye-akkumulyatory/
http://kartinki-kletochki.ru/peredelat-shurupovert-na-litievyj-akkumuljator-12/
http://orycan.ru/blog/post/Peredelka_shurupoverta_li-ion
http://mastervdome-online.ru/166-peredelka-shurupoverta-na-litievye-akkumuljatory.html

Articles alteration, batteries, lithium, screwdriver