With the rapid development of society, our lithium battery protection board is also developing rapidly. Do you know the detailed information of lithium battery protection board? Next let Xiaobian lead you to a detailed understanding of the relevant knowledge.
The common equalization charging technologies of lithium battery protection board include constant shunt resistance equalization charging, on-off shunt resistance equalization charging, average battery voltage equalization charging, switched capacitor equalization charging, buck converter equalization charging, inductor equalization charging, etc. When groups of lithium batteries are charged in series, the balanced charging of each battery should be ensured, otherwise the performance and service life of the whole group of batteries will be affected during use.
It is necessary to take a balanced situation: in the case of battery production, the storage time is longer, because different kinds of static power supply protection boards and various battery self discharge rates form the whole bundle, the battery voltage has obvious voltage difference, but the same guarantee ability, the function of balancing the battery voltage under the balanced condition, It can achieve the effect of fully charged and fully discharged battery capacity, which makes the battery exert great influence.
When the battery pack is stored for a long time after production, due to the different static power consumption of each circuit of the protection board and the different self discharge rate of each cell, the voltage of each string of batteries in the whole battery pack is not consistent, so there is an obvious voltage difference. However, under the condition of ensuring the same capacity, the balance has the function of equalizing the voltage of the battery pack, so as to achieve the full charge and high-voltage balance of the battery pack capacity The effect of full discharge makes the battery pack play a great role.
The battery itself has available capacity, but the battery system can not continue to play its due performance because of the imbalance between batteries and the limitation of the safety voltage set to protect the battery. In addition, the service life of the battery in the vehicle is shorter than that of the vehicle itself. Even if the vehicle has not reached the end of life, the battery should be replaced to meet the power performance. However, the cost of battery replacement is quite high, which restricts the development of electric vehicles to a great extent.
Balance doesn’t work: many people think that the battery is working in the middle and later stages of balance, and the actual battery pack is in poor capacity due to different battery capacity losses in the middle and later stages. The balance protection board can’t make up for the capacity of the battery, and the battery pack voltage of each string on the surface is consistent, but due to the inconsistent capacity, Low is often in the charging and discharging capacity of the battery’s single string discharge protection and overcharge protection, so the capacity of the battery is in the low capacity of the battery’s single string.
Many people think that the battery pack can be used in the middle and later stages of use. In fact, when the battery pack is used in the middle and later stages, due to the different capacity loss of each cell, there is a capacity difference. It is impossible to make up for the capacity of the cell by balancing the protection board. On the surface, the voltage of each string of the battery pack is consistent, but due to the different capacity, During charging and discharging, the single string cells with low capacity usually have over discharge protection and over charge protection first, so the capacity of the battery pack is reflected by the single string cells with low capacity.
Passive equalization generally discharges the battery with higher voltage through resistance discharge, and releases electricity in the form of heat, so as to gain more charging time for other batteries. In this way, the power of the whole system is limited by the battery with the least capacity. In the process of charging, lithium batteries generally have a upper limit protection voltage value. When a series of batteries reach this voltage value, the lithium battery protection board will cut off the charging circuit and stop charging. If the charging voltage exceeds this value, which is commonly known as “overcharge”, the lithium battery may burn or explode.
The above is the detailed analysis of the relevant knowledge of lithium battery protection board, we need to constantly accumulate experience in practice, so as to design better products for the better development of our society.