Hife Systems Ltd.

What damage does overcharging and discharging do to lithium batteries?

Number of views:489Date:2022-11-15 09:52

       I often hear manufacturers of lithium batteries say that lithium batteries can not be overcharged can not be overdischarged, otherwise it will destroy the lithium battery, so what is overcharged and overdischarged? What is the damage to lithium batteries?

      Overcharge: Overcharge refers to lithium battery overcharge, the battery charging working voltage exceeds the set working voltage, such as rechargeable battery rated current, full power ±. That is, the larger working voltage of 9V above, beyond 9V is called overcharging, overcharging what harm to rechargeable batteries? Overcharge, the battery voltage with the electrode expansion and rapid rise, will cause irreversible changes in the structure of the active material at the positive level, resulting in the dissolution of the lithium battery electrolyte, resulting in a lot of vapor, release a lot of heat, so that the battery temperature and gas pressure rose significantly, the internal diaphragm melting or closing, resulting in positive, battery positive material touching short circuit failure, there is an explosion, ignition safety risks.

      Over-discharge: Over-discharge means that the working voltage is still discharging after doing the rated current when charging and discharging, such as the rated value of ternary lithium battery charging and discharging working voltage, less than still discharging is over-discharge. What is the damage to the rechargeable battery if it is over discharged? After the battery has discharged the internal stored power and the working voltage has reached a certain value, discharging again will cause the rechargeable battery to be over-discharged, and over-discharging the battery will have a devastating adverse effect on the battery, especially when there is a large current loss or repeatedly discharging will cause more harm to the battery. Generally speaking, over-discharge will cause the gas pressure of the battery to rise, the crossover of positive and negative active substances to be destroyed, the dissolution of the lithium battery electrolyte, the buildup of negative grade lithium, the raising of the resistor, and even if the battery charge is only partially repaired, the volume will show a significant decay factor.

      How to avoid excessive over-charging or over-discharging of the battery?

      One: Apply with the lithium special type lithium battery protection board (BMS) with each other, the lithium battery protection board can carry out battery charging maintenance on the rechargeable battery, the intelligent version can also set the battery charging and discharging working voltage, can be stronger to maintain the rechargeable battery.

      Two: the application of the lithium battery charger with its matching facilities, without the use of fast charging.

      Three: When the battery voltage does the working voltage set by the lithium battery protection board, the lithium battery protection board will turn off the power to maintain the rechargeable battery, but the lithium battery will appear to be reduced, the working voltage will rise and will be slightly higher than the working voltage set by the lithium battery protection board. This time will have been without application. Constant application will cause unavoidable harm to the rechargeable battery.