# Alteration Of The Charger Of The Screwdriver For Lithium Batteries

Accumulators and batteries What is the difference between a lithium battery and a nickel-cadmium battery. Calculation of t component schemes of alteration. Operating conditions of the lithium battery. Features of alteration of batteries and chargers from different manufacturers.

## The meaning and procedure for converting screwdrivers to lithium batteries

Why do nickel-cadmium batteries fail quickly? In a garland of series-connected cans, each 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. There is no provision for monitoring and balancing the charge in individual components.

1. Each Ni-Cd bank provides 1.2V and the Li-ion 18650 3.6V.
2. The capacity of a lithium battery is 2 times that of a nickel-cadmium battery of similar size.
3. An overheated li-ion battery threatens an explosion and fire, therefore, the installation of control of the uniformity of the charge in the banks is mandatory. The manufacturer is not interested in BMS nickel-cadmium batteries.
4. Lithium cells have no memory effect, unlike Ni-Cd, they can be charged at any time and within an hour.
5. The screwdriver becomes much easier after converting the battery to li-ion, using 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 cans, the output voltage is not enough: 3.6 x 3 = 10.8 V. With 4 components, the power of the apparatus will be higher: 3.6 x 4 = 14.4 V. This will make the instrument 182 g lighter , its power will slightly increase, the capacity is solid pluses. But when dismantling, it is necessary to leave the terminals and the native thermal sensor.

## 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 type of energy source does not tolerate deep discharge and excessive charge. Therefore, 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 creating a device using lithium batteries to facilitate a hand tool and increase its performance. Lithium 18650 batteries are most suitable for these purposes.

When selecting components, it should be taken into account that the starting current of the screwdriver is high, it is necessary to choose the appropriate 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 melt glue, flux for soldering TAGS, solder.
• Jumpers or thick insulated wire with a cross section of at least 0.75 squares, cut for bridges.

The procedure for converting a screwdriver for 18650:

• Disassemble the case and remove a bundle of 12 Ni-Cd cells from the container.
• Remove the garland, leaving the connector with leads and. Instead of a thermal 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, do not warm up the covers. Work pointwise.
• Connect balancing points to the controller according to the diagram. The connectors are provided on the board.
• Connect the assembly to the plus and minus terminals.
• Check the functionality of the circuit. If everything works, the assembled battery, place the controller in the socket, secure with 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 redesigned using a set of 18650 batteries in the amount of 2 cells.

## Alteration of the Hitachi 12 V screwdriver to lithium batteries 18640

Features of alteration of the Hitachi 12 V 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 of the partition to fit 1 element tightly.

You need to get a flux, 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 serve 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 to one side, connected with solder to the leads from thick wires and filled with hot melt glue over the assembly.

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.

## Converting a screwdriver to lithium batteries 18650

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

## Accumulators and batteries

Energy storage information website

## Converting a Makita screwdriver to a 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. Alteration will give the old tool new opportunities: power, as the operating voltage rises to 10.8 V.

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. A built-in balancer is used here.

The parameters of the controller should accompany the operation of the instrument when the operating current rises to 10-20 A. The Sony VTC4 30 A board, designed for a capacity of 2100 A / h, can ensure operation without shutdown. Of the 20 amperes, the Sanyo UR18650NSX accepting energies of 2600A / h is suitable. The board is needed 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.

A step-by-step instruction on how to convert a Makita screwdriver to lithium batteries looks like this.

1. You can disassemble the battery with glue if you tap the junction with a soft-headed hammer while weighing. The direction of impact is downward, into the joint on the lower part of the body.
2. Take only contact plates from the old assembly, carefully disconnecting them from the battery. Leave the sensor and breaker.
3. Solder 3 elements in series using TAGS flux and insulated jumpers. The wire cross section must be greater than 0.75 mm2.
4. Assemble the circuit with the controller, and connect the power supply to the contact connectors with 1.5 square wires.
5. Check the functionality of the circuit and reassemble the case by placing it on the glue again.

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 for use.

## Alteration of the Hitachi 12V screwdriver for lithium batteries 18640

Features of alteration of the Hitachi 12 V 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 of the partition to fit 1 element tightly.

You need to get a flux, 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 serve 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 to one side, connected with solder to the leads from thick wires and filled with hot melt glue over the assembly.

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.

## Converting a screwdriver to lithium batteries 18650

Every craftsman faces the problem of reduced tool performance, or complete failure due to the battery. Manufacturers use nickel-cadmium batteries in 12, 14, 18 volt screwdrivers. The sequential assembly of several elements creates the required voltage. Replacing nickel-cadmium batteries with lithium batteries extends battery life, making the design easier. 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 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 type of energy source does not tolerate deep discharge and excessive charge. Therefore, 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 creating a device using lithium batteries to facilitate a hand tool and increase its performance. Lithium 18650 batteries are most suitable for these purposes.

When selecting components, it should be taken into account that the starting current of the screwdriver is high, it is necessary to choose the appropriate 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 melt glue, flux for soldering TAGS, solder.
• Jumpers or thick insulated wire with a cross section of at least 0.75 squares, cut for bridges.

The procedure for converting a screwdriver for 18650:

• Disassemble the case and remove a bundle of 12 Ni-Cd cells from the container.
• Remove the garland, leaving the connector with leads and. Instead of a thermal 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, do not warm up the covers. Work pointwise.
• Connect balancing points to the controller according to the diagram. The connectors are provided on the board.
• Connect the assembly to the plus and minus terminals.
• Check the functionality of the circuit. If everything works, the assembled battery, place the controller in the socket, secure with 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 redesigned using a set of 18650 batteries in the amount of 2 cells.

## The meaning and procedure for converting screwdrivers to lithium batteries

Why do nickel-cadmium batteries fail quickly? In a garland of series-connected cans, each 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. There is no provision for monitoring and balancing the charge in individual components.

1. Each Ni-Cd bank provides 1.2V and the Li-ion 18650 3.6V.
2. The capacity of a lithium battery is 2 times that of a nickel-cadmium battery of similar size.
3. An overheated li-ion battery threatens an explosion and fire, therefore, the installation of control of the uniformity of the charge in the banks is mandatory. The manufacturer is not interested in BMS nickel-cadmium batteries.
4. Lithium cells have no memory effect, unlike Ni-Cd, they can be charged at any time and within an hour.
5. The screwdriver becomes much easier after converting the battery to li-ion, using 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 cans, the output voltage is not enough: 3.6 x 3 = 10.8 V. With 4 components, the power of the apparatus will be higher: 3.6 x 4 = 14.4 V. This will make the instrument 182 g lighter , its power will slightly increase, the capacity is solid pluses. But when dismantling, it is necessary to leave the terminals and the native thermal sensor.

## Accumulators and batteries

Energy storage information website

## Converting a Makita screwdriver to a 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. Alteration will give the old tool new opportunities: power, as the operating voltage rises to 10.8 V.

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. A built-in balancer is used here.

The parameters of the controller should accompany the operation of the instrument when the operating current rises to 10-20 A. The Sony VTC4 30 A board, designed for a capacity of 2100 A / h, can ensure operation without shutdown. Of the 20 amperes, the Sanyo UR18650NSX accepting energies of 2600A / h is suitable. The board is needed 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.

A step-by-step instruction on how to convert a Makita screwdriver to lithium batteries looks like this.

1. You can disassemble the battery with glue if you tap the junction with a soft-headed hammer while weighing. The direction of impact is downward, into the joint on the lower part of the body.
2. Take only contact plates from the old assembly, carefully disconnecting them from the battery. Leave the sensor and breaker.
3. Solder 3 elements in series using TAGS flux and insulated jumpers. The wire cross section must be greater than 0.75 mm2.
4. Assemble the circuit with the controller, and connect the power supply to the contact connectors with 1.5 square wires.
5. Check the functionality of the circuit and reassemble the case by placing it on the glue again.

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 for use.

## Homemade charger for lithium-ion batteries screwdriver

In a previous article, I considered the issue of replacing nickel-cadmium (nickel-manganese) NiCd (NiMn) screwdriver batteries with lithium ones. There are a few rules to consider when charging batteries.

Lithium ion batteries of 18650 size can generally be charged up to 4.20V per cell with a tolerance of no more than 50mV, because an increase in voltage can damage the battery structure. The battery charge current can be 0.1xC to 1xC (here C is the capacity). It is better to select these values ​​from the datasheet. I used Samsung INR18650-30Q 3000mAh 15A batteries in the rework of the screwdriver. We look at the datasheet-charging current 1.5A.

The most correct would be to charge lithium batteries in two steps according to the CCCV method (constant current, constant voltage).

The first step is to provide a constant charge current. The current value is 0.2-0.5C. I used a 3000 mA / h battery, which means the nominal charge current will be 600-1500 mA. After the can is charged at a constant voltage, the current is constantly decreasing.

The voltage on the battery is maintained within 4.15-4.25V. The battery is charged if the current drops to 0.05-0.01C. Taking into account the above, we use electronic boards from Aliexpress. CC / CV current-limited step-down board on XL4015E1 or LM2596. A board based on XL4015E1 is preferable as it is more convenient in settings.

Specifications XL4015E1.
Maximum output current up to 5 A.
Output voltage: 0.8V-30V.
Input voltage 5V-32V.
The board on the LM2596 has similar parameters, only the current is up to 3 A.

List of tools and materials.

-adapter 220 \ 12 V, 3 A, 1 piece;
-standard screwdriver charger (or power source);
-charge board CC / CV for XL4015E1 or LM2596.1pcs;
-connecting wires; soldering iron;
-tester;
-plastic box for charge board 1pc;
-minivoltmeter 1 piece;
-variable resistor (potentiometer) for 10-20 kOhm, 1 piece;
-power connector for the battery compartment of the screwdriver. 1 pc.

Step one. Assembling the charger of the screwdriver batteries on the adapter.

We have already chosen the cccv board above. As a power source, you can use any one with such parameters. The output voltage is not lower than 18 V (for the 4S circuit), the current is 3 A. In the first example of making a charger for lithium-ion batteries in a screwdriver, I used an adapter 12 V, 3 A.

Previously, I checked what kind of current it can give a feast to the rated load. I connected an autolamp to the output and waited half an hour. It gives out freely without overloading 1.9 A. I also measured the temperature on the radiator of the transistor.40C. Quite normal mode.

But in this case, there is not enough tension. This can be easily fixed with just one penny radio component. A 10-20 kΩ variable resistor (potentiometer). Let’s consider a typical adapter circuit.

The circuit has a controlled zener diode TL431, it is in the feedback circuit. Its task is to maintain a stable output voltage in accordance with the load. It is connected to the positive output of the adapter through a divider of two resistors. We need to solder to the resistor (or solder it completely and solder it in its place, then the voltage will be regulated downwards) which is connected to pin 1 of the TL431 zener diode and a variable resistor to the negative bus. Rotate the potentiometer axis and set the desired voltage. In my case, I set it to 18V (small margin from 16.8V to drop on the CC / CV board). If you have the voltage indicated on the bodies of the electrolytic capacitors standing at the output of the circuit is greater than the new voltage, they may explode. Then you need to replace them with a margin of 30% in voltage.

Next, we connect the charge control board to the adapter. We set a voltage of 16.8 V with a trimmer resistor on the board. Another trimmer resistor sets a current of 1.5 A, we first connect the tester in ammeter mode to the board output. The lithium-ion screwdriver assembly can now be connected. Charging was normal, the current dropped to a minimum by the end of the charge, the battery was charged. The temperature on the adapter was in the 40-43C range, which is quite normal. In the future, you can drill holes in the adapter body to improve ventilation (especially in summer).

The end of the battery charge can be seen by the on-board LED on the XL4015E1. In this example, I used another board on the LM2596, as I accidentally burned the XL4015E1 during experiments. I advise you to do better charging on the XL4015E1 board.

Step two. Assembling the charger circuit of the screwdriver batteries on a standard charger.

I had a regular charger from another screwdriver. It is designed to charge nickel-manganese batteries. The task was to charge both nickel-manganese and lithium-ion batteries.

This was solved simply. I soldered to the output wires (red plus, black minus) wires to the CC / CV board.
The open circuit voltage at the output of the standard charger was 27 V, which is quite suitable for our charging board. Further, everything is the same as the version with the adapter.

Here we see the end of charging by the change in the color of the LED (switched from red to green).

I placed the CC / CV board itself in a suitable plastic box, leading the wires out.

If you have a standard charger on a transformer, then you can connect the CC / CV board after the rectifier diode bridge.

The method of converting the adapter is within the power of beginners and can be useful for other purposes, as a result we will get a budgetary unit for powering various devices.