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.
Conversion of 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, 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.
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.
- 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.
- Take only contact plates from the old assembly, 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 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.
To unscrew the module, select a screwdriver that is suitable in shape and length. It is very easy to disassemble the unit, for this you need to unscrew the screws and detach the case. It is necessary to remember from which holes the screws were unscrewed in order to screw them into place during assembly.
The battery case is fastened to the device in 3 ways:
- With glue.
- Snap fastening.
- Using screws.
Some models use several combinations of fasteners with different types of fasteners: for example, screws and glue.
How to disassemble a screwdriver battery
To understand how to disassemble the battery of a screwdriver and not damage it, you should adhere to some simple rules. The battery is disassembled in order to replace the batteries or transfer it to another type of nutritional element: for example, change the nickel batteries to lithium ones. Disassembly operations must be accurate, accurate to avoid damage to other important elements of the screwdriver and to ensure proper operation of the tool in the future.
- Preparation for work
- Mount types
- Fastening with glue
- Snap fastening
- Using screws
- Features of the battery in screwdrivers
Replacing batteries in a screwdriver with lithium
What do you need to estimate before starting work?
Also, more lithium cells will give more capacity. This means more operating time of the screwdriver.
Lithium battery cells 18650
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 cells. Connect them two by two in 4 parallel assemblies, and then connect them in series. As a result, you will be able to increase the battery capacity. But not every case will be able to pack 8 cans of 18650.
And the last preparatory stage is choosing a controller. According to its characteristics, it must correspond to the rated voltage and discharge current. That is, if you decide to assemble a 14.4 volt battery, then choose a controller with this voltage. The working discharge current is usually chosen to be two times less than the maximum permissible current.
Charge-Discharge Controller Board
All pros and cons of converting a screwdriver battery to lithium cells
First you should think about whether I need this alteration? After all, it will be a frank self-propeller and in some cases can lead to failure of both the battery and the screwdriver itself. Therefore, let’s consider all the pros and cons of this procedure. It is possible that after that some of you will decide to abandon the conversion of the Ni─Cd battery for a screwdriver to lithium cells.
Replacement battery for Makita screwdriver
Battery appearance. Looks like the original, glossy plastic, high quality casting. If not for the new species, I would have thought it was the original. Well done. The only thing that catches your eye is another sticker that is not branded. And under the sticker there are screws, the original is more difficult to disassemble
Compare with the original sticker (original: 1222 cadmium 2.0Ah) The old battery is already well-worn, has worked well, the sticker will not rub off or wash. The black cross on it seems to hint))))
Battery marking: 3.0Ah, NiMH. The old one was at 2.0Ah and NiCd. This is a big plus, I hope it will be positive in my work. By the way, the old one has been working for 15 minutes, then back to the base.
Like any Chinese device, it is better to disassemble it before turning it on. So to speak, beware of possible problems.
To disassemble, peel off the sticker and unscrew
three four screws. This photo has already been.
Gently pull out the case, the cells and contacts of the battery open.
The photo clearly shows the thermal sensor
The battery assembly makes a positive impression, the package of cells is monolithic. Above is a plastic contact holder.
Here is the labeling of the cells used Ni-MH SCI2017-B.
By the way, the cells are welded with a tape qualitatively, the block seems to be monolithic, does not dangle, drips, traces of rust, no flux.
It happens worse)))
Satisfied in principle. Plus and minus in place, as shown by the tester. I still trust him)))).
The verdict can be included.
And that’s what has been done.
Two batteries side by side. Weathered and new (left dirty old, right shiny new)
I screwed a couple of self-tapping screws very well, good torque. The battery is fresh, and asks for work. By the way, it was almost fully charged.
I drove a little screwdriver until the battery was discharged. A total of about 4 hours of OSB / plywood sheathing work. For comparison, the old battery lasted 18 minutes, the second battery from the kit no longer pulls such work.
P.S. I have been using the battery for over a month now. So far, no minuses have been identified. After a while I will try to do the capacity test again and compare. And I will try to sort out one old battery for lithium cells. It turned out all the same cheaper than offline.
12V 3000mAh Ni-MH battery is a replacement for original series batteries:
1220 1222 1233S 1233SA 1233SB 1235A 192598-2 192681-5 193981-6 638347-8 638347-8-2 PA12
Compatible screwdriver models:
Makita 1050 Series
Makita 1050D, Makita 1050DA, Makita 1050DRA, Makita 1050DWA, Makita 1050DWD
Makita 4000 Series
Makita 4013D, Makita 4191D, Makita 4191DWA, Makita 4191DZ
Makita 4331D, Makita 4331DWAE, Makita 4331DWD, Makita 4331DWDE, Makita 4331DZ
Makita 5000 Series
Makita 5093DWD, Makita 5093DZ, Makita 5093D, Makita 5093DWA
Makita 6200 Series
Makita 6213D, Makita 6213DWAE, Makita 6213DWBE
Makita 6216D, Makita 6216DWBE, Makita 6216DWDE
Makita 6217D, Makita 6217DWDE, Makita 6217DWDLE
Makita 6223D, Makita 6223DE, Makita 6223DW, Makita 6223D, Makita 6223DW, Makita 6223DWE
Makita 6227D, Makita 6227DW Makita 6227DWBE, Makita 6227DWE, Makita 6227DWLE
Makita 6270D, Makita 6270DWAE, Makita 6270DWLE, Makita 6270DWALE, Makita 6270DWE, Makita 6270DWPE
Makita 6271D, Makita 6271DWAE, Makita 6271DWE, Makita 6271DWPE, Makita 6271DWPLE
Makita 6300 Series
Makita 6313D, Makita 6313DA, Makita 6313DWAE, Makita 6313DWBE
Makita 6314DWBE, Makita 6316D, Makita 6316DWA, Makita 6316DWAE, Makita 6316DWB, Makita 6316DWBE
Makita 6317D, Makita 6317DWAE, Makita 6317DWDE, Makita 6317DWDRE, Makita 6317DWFE
Makita 6319D, Makita 6319DWFE, Makita 6327DWE
Makita 6800 Series
Makita 6835D, Makita 6835DA, Makita 6835DWA, Makita 6835DWAE, Makita 6835DWB, Makita 6835DWD
Makita 6900 Series
Makita 6914D, Makita 6914DWDE
Makita 6916D, Makita 6916DWDE, Makita 6916FDWDE, Makita 6916FDWDE1
Makita 6917D, Makita 6917DWDE
Makita 6918D, Makita 6918DWA, Makita 6918DWAE, Makita 6918DWD
Makita 6918DWDE, Makita 6918DWF, Makita 6918DWFE, Makita 6918FDWDE
Makita 6980FD, Makita 6980FDWDE
Makita 8200 Series
Makita 8270DWAE, Makita 8270DWALE
Makita 8400 Series
Makita 8413D, Makita 8413DWAE, Makita 8413DWDE
Makita 8413DWFE, Makita 8414DWFE
Makita DA Series
Makita DA312D, Makita DA312DWA, Makita DA312DWD
Makita DA312DWF, Makita DA312DZ, Makita ML120, Makita ML121 (Head Lamp)
Makita ML Series
Makita ML120, Makita ML121 (Head Lamp)
Makita ML122, ML123 (Fluorescent Automotive Light)
Makita UB Series
Makita UB120D, Makita UB120DWA, Makita UB120DWB
Makita UB121D, Makita UC120D, Makita UC120DA
Makita UC Series
Makita UC120DR, Makita UC120DRA, Makita UC120DW, Makita UC120DWA
Makita UC120DWAE, Makita UC120DWD, Makita UC170D, Makita UC170DWD
Makita VR Series
Makita VR250D, Makita VR250DA, Makita VR250DWAE, Makita VR251D
Makita VR251DWDE, Makita ML123 (Fluorescent Automotive Light)
Why the battery of the screwdriver does not charge causes and elimination
The reasons for the absence or weak level of charge, as well as ways to eliminate the malfunction, are different:
- There is no contact between the terminals of the charger and the battery. This is a consequence of the fact that the memory plates are bent. Gently bend the plates back to working condition.
- Oxidation of terminals or dirt adhering to them. Contacts are cleaned and wiped with alcohol.
- Failure of one of the cans. Disassemble the battery pack housing by removing the cover (unscrew the screws or remove the latches). Call each jar with a tester for voltage or discharge current. With tension, it is either easier or not, but this method does not always work. The discharge current is measured at the load resistor of a faulty can, it is an order of magnitude lower than that of a working one. After diagnostics, the faulty jar is separated from the serviceable ones, and a new one is installed in its place, exactly of the same type, and with the same polarity orientation relative to the other elements.
There is one more reason for the lack of charge, but it is characteristic only for nickel-cadmium batteries, the memory effect has worked, and the battery does not charge, although its resource has not yet been exhausted. In order not to bring it to this, it is important to carry out the charging correctly.
What to do if the screwdriver battery does not charge
Cordless screwdrivers are more convenient to use than mains. They are distinguished by their mobility, independence from the presence of an outlet at hand, the length of the cord. The only drawback is that you need to monitor the charge level for timely recharging. But not all types of batteries allow you to do this, and at the most inopportune moment the screwdriver stops working. And, unfortunately, there comes a time when the battery stops charging.
There are three types of tool batteries:
- Nickel Cadmium (NI-Cd). The older generation, which is still equipped with household screwdrivers. Affordable price, good ratio of size and capacity (rather compact), keep the charge in an idle state for a long time. Lack of memory effect. If you recharge without a full discharge, then information about an incomplete volume is accumulated, it interferes with giving a charge until the real resource is exhausted.
- Nickel Metal Hydride (Ni-Mh). An improved analogue of nickel-cadmium batteries with a cleaner production technology. Although the memory effect is present, it is weaker. The main disadvantage is quickly discharged during storage.
- Lithium ion. The most advanced type, which is gradually replacing other types in the segment of professional / semi-professional electric hand tools. High capacity, virtually no memory, durability, low self-discharge in storage mode. The only drawback is the high cost compared to other analogues.