36V 19.8Ah Low Temperature Lithium Ion Battery Design Solution of Electric Wrench

Electric wrench is a mechanized construction tool for assembling screw elements and bolts. It has the function of automatic torque control. It is widely used in the erection of bolting and welding composite structure bridge, assembling of factory, tower, chemical device, metallurgical equipment, power equipment, large mechanism, lifting appliance, vehicle assembly, and the position having strict requirements of threaded fastener torque and axial tensile. The product is combined by host machine and controller. The host machine adopts mono-phase series electromotor with double insulation and decelerating device, which has novel structure, good security and nice reliability. Because of adopting static torsion structure, it has smooth operation, no vibration, no impact and low noise. The operators are not affected by counter torque, so that they will have low labor intensity. The former electric wrench relies on AC power supply, which is not convenient for operators. The battery of Large Power has advanced technology and deep comprehension of battery charging and discharging. Large Power has produced an intelligent rechargeable lithium ion battery designed for portable electric wrench, which greatly improves the efficiency and flexibility of traditional lashing operation. This lithium ion battery adopts lithium cobalt oxide cell with high energy ratio and low temperature discharging performance. It can work for a long time at -40℃ and charge at any time, which has low self-discharge rate, no memory effect, efficient charging mode and completed protection function.

Battery design requirements of electric wrench

1、Super low temperature function: meet the requirement of low temperature operation on northwest district at -40℃.

2、Individual output terminal: adopt individual charging and discharging output mode ofspecial connector, which can charge and discharge together with individual terminal.

3、LCD capacity display: display the capacity of battery during charging and discharging at any time so as to monitor the battery capacity.

Battery design solution of electric wrench

1、Types: adopt 18650/2200mAh/3.7V rechargeable lithium ion battery with high energy density, low temperature performance and good security.

2、Battery protection system (BMS): it is protective circuit of rechargeable battery pack. Because of the chemical characteristics of lithium ion battery, it needs protective function of overcharge, over-discharge, short circuit, over current and over temperature so as to avoid combustion, explosion and other dangers.

3、Protection IC: it is the chip has main protective function in the design scheme. The chip monitors the cell on the functions of overcharging, over-discharging, overcurrent, short circuit, etc. at any time, which helps the battery works under safe, stable and efficient circumstance.

4、MOSFET: it works as the switch in protective circuit to make sure that the voltages of two ends won’t be up and down, so that the voltage will be stable.

5、LCD capacity display: it has LCO voltage display inside and can display the capacity status of battery pack at any time.

Encapsulation of battery pack (aluminum alloy housing)