How do you know if a battery you receive is a good quality?Today this video will help you to know more about the lithium battery.It is a good way for newbie to identify the quality of the battery you purchase.
Nowadays there are a variety of lithium battery in the market,different brand,models,material,price,capacity.
Lithium battery are mainly divided into:LFP,LNO,LMO,LCO,NCM,NCA.We use NCA.
We use 18650.18 stands for the diameters is 18 milimeters,65 stands for the height is 65 milimeters,0 stands for cylinder.You will see the brand,LG,and some are samsung or other unknown brand names showed on the cells,2600mAh or 3200mAh,the voltage is 3.6V,max charge voltage is 4.2V.A lot of bad reputation suppliers will use unknown brand battery cells instand of famous brand cells,but with the high price.They are sure that no one will open the battery box to identify the truth.
We can calculate the battery capacity.But the battery capacity in the quotations from some suppliers is not correct.This is unprofessional.Today I am going to show you how to calculate the capacity.The space in different battery cases are not the same,some can fit 52 units cells,some can fit 65 or78.Each battery voltage is 3.6V or 3.7V.If one battery voltage is 48V,48V is devided by 3.7V,3.7 is each battery cells voltage,is 13.13 means 13 series.If one battery can fit 52 battery cells,52 is devided by 13 is 4. 4 means 4 parallel.13 series times 4 parallel is 52 units battery cells.Each battery capacity is 2600mAh or 3200mAH(3500,2500,2900).3200mAh times 4 is 12.8Ah.The battery capacity is 12.8ah.If one battery can fit 65 units battery cells,3200mAh times 5 parallel is 16Ah.Can you learn it?
Let’s talk about the BMS.(BATTERY MANAGEMENT SYSTEM),what’s the function of BMS?The most important part is protecting the battery.The quality is totally not the same in the market.If the quality is not good,it will cause many problems.
The unbalanced discharge of the battery is easy to heat up,it will burn or explode in serious cases.
Second, The technical principle of short-circuit protection is unreasonable, and the metal of the connector melts during short-circuit protection.
Third, The battery discharge is not balanced, resulting in the power is not durable, easy to break.
There is the battery suppliers’ problems,the wiring of the BMS is in disorder,and the wire harness is squeezed by the battery box,it can’t be charged and discharged in serious cases.
Poor wiring harness welding will lead to false welding, Unreliable connection, heat.
The poor quality of the nickel sheet will lead to increased internal resistance and heat, and the heat will be out of control in serious cases.
If the support material is not good, it will heat and melt.