Cordless type of power allows the tool to work for a long time without interacting with the electrical network. This technology is also used for various types of screwdrivers. A correctly selected battery will optimize the operation of the device and extend its service life.
For a screwdriver may be selected one of three types of batteries:
- nickel cadmium (NiCd);
- nickel metal hydride (NiMH);
- lithium-ion (Li-Ion).
Models of the first type are large. They are distinguished by low cost and uninterrupted operation at negative and positive temperatures. Such devices are charged a large number of times, but due to the memory effect they need to be stored in a fully discharged form. Charge should also be done after the battery is fully exhausted.
The effect of memory is called the decrease in battery capacity, which reduces the duration use of the device between charging procedures. The indicator of the remaining charge is fixed by the battery, and after recharging it will consume energy to this level. Therefore, it is important to fully discharge the battery when working with the tool.
NiMH batteries are lightweight and environmentally friendly to use. They are able to work for a long time without additional recharging. Models of this type are also equipped with a memory effect, but it does not affect battery performance so much. A significant disadvantage of this battery line is intolerance to negative temperatures. When the indicator on the thermometer drops to minus two degrees, the battery gradually loses its charge. It is necessary to store the instrument with this type of power in a warm room, discharging the battery completely.
Lithium-ion batteries appeared in 1991 and have become the most popular and convenient power source. The memory effect in them is completely absent, the batteries have high capacity and may take a long time hold a charge. The weight of the battery is almost two times less than that of analogues. Recharging can be carried out at any battery performance. Professional screwdriver models are most often equipped with this type of battery.
When choosing a battery, you should pay attention to a number of characteristics:
- battery capacity;
- charging speed;
The battery life, measured in ampere-hours, determines the operating time of the device without additional charge. Household tools have a capacity of 1.3−2 A / h, and professional models. over 2 A / h.
The short charging time allows you to increase the pace of working with the tool. Inexpensive household appliances charge 2−12 hours. For more expensive professional models, 0.5-1 hours of charging is sufficient. Accelerated recharge of energy is provided by lithium batteries and impulse devices for charging.
The battery may have a voltage of 3–36 volts. With the same torque, the voltage values of the tool can vary. Batteries with high voltage maintain the maximum power indicator of the device for a longer time until the charge drops.
Battery Selection Features
The choice of battery type depends on the scope of the tool. If it will be used in production, the following characteristics will be of greatest importance:
- trouble-free operation for a long time;
- immunity to temperature and weather conditions;
- fast charge;
The best choice for such tasks may be a nickel-cadmium battery. It performs well when working with equipment at high power. Having bought a spare battery, you can continue to work until the battery is completely discharged without interruptions in operation.
For household power tools episodic use is characteristic. A long-lasting and reliable choice can also be a nickel-cadmium battery. To avoid additional difficulties with full discharge and battery training, you can purchase a lithium-ion model for home use. This option is suitable for screwdrivers with medium and low power. Batteries like Li-Ion have a large capacity, are able to charge at any level of the battery, have low weight and modest dimensions.
In terms of cost, the most low-cost models are nickel-cadmium-based devices, NiMH take second place, and lithium-ion models will cost more than others.
Popular battery models for Makita screwdriver
Makita cordless screwdrivers made in Japan have established themselves as reliable and high-quality products that combine modern technology and the best price. The versatility of Makita tools allows them to be used for industrial and domestic needs. A number of batteries are available for this brand of screwdrivers.
- The cubic model Makita 1202 192536−4 is the best choice for price and quality. The battery belongs to the nickel-cadmium type, has a voltage of 12 V, a capacity of 2 A / h, weighs 0.7 kg. The device has a clip shape. Price. 9 thousand rubles.
- Model Makita P. A. 09 193977−7 has a voltage of 9.6 V, a capacity of 1.3 A / h. Clip-on battery type Ni-Cd. The device weighs 0.5 kg. Price 2700 p.
- Makita 1435 193060−0 refers to nickel-metal hydride type batteries. The device voltage is 14.4 V, the battery capacity is 2.8 A / h, and the weight is 0.8 kg. Price. 5200 p.
- The device Makita 1234 193100−4 type NiMh, has a voltage of 12 V, a capacity of 2.5 A / h. The weight of the battery is 0.7 kg. Price. 6400 p.
- The lithium-ion battery Makita B. L. 1013 194550−6 has a voltage of 10.8 V, weighs 0.2 kg. The battery has a capacity of 1.3 Ah. A distinctive feature of the battery is a shock-absorbing housing made of durable material. The price of the device is 2500 p.
- Makita BL 1430 194065−3 has a capacity of 3 A / h, voltage of 14.4 V, has the shape of a slider. Type. Li-Ion, device weight. 0.6 kg. Price. 7 thousand p.
Energy Storage Information Site
Each master is faced with the problem of reducing the operability of the tool, or a 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 desired voltage. Replacing lithium nickel-cadmium batteries increases the battery life, making the design easier. Mandatory installation of the BMS board adds reliability. Therefore, the alteration of the screwdriver on lithium batteries, mainly on the form factor 18650, is justified.
The meaning and procedure for converting screwdrivers to lithium batteries
Why do nickel-cadmium batteries fail quickly? In a garland of cans connected in series, each is distinctive. The chemical process is individual, the charge in closed systems is different. If there is a malfunction in one bank, the design does not provide the desired voltage. The control system and charge balancing in individual components is not provided.
Video: Alteration Akb Screwdriver Makita Makita
- Each Ni-Cd bank gives 1.2 V, and li-ion 18650 gives 3.6 V.
- The capacity of a lithium battery is 2 times more than a nickel-cadmium, close size.
- An overheated li-ion battery threatens to explode and catch fire, so setting charge uniformity control in banks is mandatory. BMS is not installed in nickel-cadmium batteries. the manufacturer is not interested.
- Lithium cells do not have a memory effect, unlike Ni-Cd, you can charge them at any time and for an hour.
- The screwdriver becomes much easier after the alteration of the battery on li-ion, using 18650 cans.
There are only two obstacles to remaking a screwdriver for lithium batteries. it is impossible to work with it in the negative. The capacity of the cans drops, 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 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 elements.
Suppose you need to remodel 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 device will be higher: 3.6 x 4 = 14.4 V. In this case, the tool will become lighter by 182 g , its power will slightly increase, capacity is a solid plus. But when dismantling, it is necessary to leave the terminals and the native temperature sensor.
Converting a screwdriver to lithium batteries 18650 14 V
When remodeling screwdrivers of different capacities and flashlights from Ni-Cd to Li-ion, they often use 18650 form factor batteries. They easily fit into a container or socket, since instead of two or three relatives they install one lithium one. Alteration of the screwdriver battery should be carried out taking into account the characteristics of lithium batteries at 18650.
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 the balancer. The meaning of the alteration of a screwdriver with a voltage of 14.4 V is to create a device using lithium batteries to facilitate a hand tool and increase its performance. Most suitable for these purposes are lithium batteries 18650.
When selecting components, it should be noted that the starting current of the screwdriver is high, you must select the appropriate BMS for the desired number of cans and at least 30 A. To remake the screwdriver with a lithium battery, you need to stock up with a good soldering iron, non-acid flux and thick wires to make jumpers.
- 4 lithium-ion cans
- 4-bank li-ion battery controller, CF-4S30A-A is well suited. It has a built-in balancer that controls the charge of each element.
- Hot melt adhesive, TAGS solder flux, solder.
- Heat-resistant adhesive tape;
- Connection jumpers or thick wire in insulation with a cross section of at least 0.75 square, cut for bridges.
The procedure for remaking a screwdriver for 18650:
- Disassemble the housing and remove from the container a bundle of 12 Ni-Cd elements.
- Remove the garland, leaving the connector with the conclusions "" and "-". Instead of a temperature sensor, a thermocouple from the controller is installed.
- Solder the assembly, given that acid cannot be used, only neutral flux and pure solder. During the connection period, do not heat the lids. Work pointwise.
- Connect the balancing points to the controller according to the diagram. Connectors are provided on the board.
- Connect the assembly to the plus and minus terminals.
- Check the operation of the circuit. If everything works, the assembled battery, place the controller in the socket, fasten with sealant.
If the memory is not universal, additional alteration is required. 12 V screwdrivers with a universal charger are assembled in the same way, but a protective connection scheme of 3×18650 3.7 V for lithium batteries is used. In the same way, a screwdriver is reworked using a battery kit of 18650 in the amount of 2 elements.
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 components 18650. Alteration will provide the old tool with new features: increase the duration of work on a single charge , will add power, since the operating voltage rises to 10.8 V.
For the design, you will need to use BMS, a control controller that supports the mode of operation of lithium cells within the operating limits. With this breaker, the charging of each can will be uniform without exceeding 4.2 V, the lower voltage is 2.7 V. The built-in balancer is used here.
The parameters of the controller should accompany the operation of the tool when the operating current is increased to 10-20 A. A 30 V Sony VTC4 board with a capacity of 2100 A / h can ensure operation without shutting down. From 20 amperes, Sanyo UR18650NSX is suitable for receiving energy of 2600A / h. The board is needed for 3 elements, which is marked in the 3S classification. In this case, the board should have 2 contacts, plus and minus. If the findings are marked with the letters "P-", "P", "C-", they are intended for later models of screwdrivers.
A step-by-step instruction for converting a Makita screwdriver to lithium batteries looks like this.
- It is possible to disassemble the battery on glue, if on weight tap the place of connection with a hammer with a soft head. Direction of impact down to the joint along the lower part of the body.
- Take only contact plates from the old assembly, carefully disconnecting them from the battery. Sensor and disconnect must be left.
- Solder 3 elements in series using TAGS flux and insulation 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 connectors with 1.5 square wires.
- Check the operation of the circuit and assemble the housing, again putting it on the glue.
In a screwdriver with an old DC9710 charger, after the 18650 lithium battery is charged, the red LED on the panel will turn off. The charge level is monitored by the built-in controller.
The Makita DC1414 T charger is used to charge power supplies of 7.2-14.4 V. 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 necessary charge is already there. The screwdriver is ready to work.
Converting a 12 V Hitachi screwdriver to 18640 lithium batteries
Features of the conversion of a 12 V Hitachi screwdriver to lithium batteries. A very compact socket for battery cells designed for finger cells. Therefore, you should prepare a place for 18650 elements. 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 melt adhesive. Install lithium batteries in a screwdriver during alteration must be through a protective controller. It should serve 3 cells 18650, voltage of 3.7 V and is designed for 20-30 amperes.
Remove the old battery from the socket, carefully disconnect the contacts in the assembly with the temperature sensor and power indicator. Strip and sign contacts. They should be brought out in one direction, connected by solder to the leads from thick wires and fill the assembly with hot glue.
Assemble an energy source with one of the controllers, designed for 3 elements. Assemble a serial circuit of 3 Li-ion elements. Connect the controller. Alteration of the lithium 12-volt battery is completed when the design is installed in the unit, is fixed, and the charge indicator lights up. After fully charged, the measurements show 12.17 volts in the external network. But this is enough for trouble-free long-term operation of the device.
Alteration of the Interskol screwdriver to 18650 lithium batteries
Sooner or later, the nickel-cadmium assembly of 15 cans fails. One or two elements are lazy, and it is already impossible to get the output voltage. Modern DS “Interskol” on lithium batteries serve much better. Alteration of a screwdriver on lithium batteries 18 volt masters mastered.
You need 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 factory thermistors, extending the wires. During installation, create a contact pad, insert the assembly, check operation, fix it. Assembly features wizard tips are given in detail in the video. Here is full details of the rework of the 18-volt lithium screwdriver
In this post I’ll tell you how I transferred my Makita 6271D screwdriver from Ni-Cd to Li-Ion batteries.
My knowledge for this was not enough, so I was guided by this (in my opinion good) report. "link".
My reasons for converting a screwdriver to lithium:
1. Established batteries no longer hold a charge. Enough for 10 minutes. not intense work.
2. The cost of new "branded" Battery to say the least is not humane.
3. Low load on the screwdriver. Use as needed 1-2 times a month. But nickel-cadmium batteries do not like this mode.
4. There is no need to work with the shurik in low temperature conditions. What kills lithium batteries.
5. The presence of a power supply from a laptop (19 V, 1.5 A).
What was required for the alteration: