Discharging a lithium cell this low is stressful to the cell and reduces cell lifetime. A good battery protection circuit will also provide over-discharge protection. Even protection circuit is added on lithium batteries, users should avoid over charge and over discharge during the use of lithium batteries.
The over-discharge refers to the behavior of continuing to discharge a battery when it reaches the discharge cut-off voltage , . The over-discharge can occur in a variety of situations, such in cells without BMS in various aerospace and implantable medical devices.
Over-discharge protection threshold The over-discharge protection threshold also has an impact on capacity/charge and cell life. A battery will have more capacity per charge if it is discharged all the way. However, this is stressful on the battery and will reduce the lifetime of the battery.
To combat over-discharge, deploying protective mechanisms such as Battery Management Systems (BMS), Protection Circuit Modules (PCM), or Printed Circuit Boards (PCB) is vital. Avoiding full discharge also plays a pivotal role in preventing this damaging scenario.
Overdischarge protection in battery chargers is a critical feature that prevents the battery from being discharged below a safe voltage level. This protection is essential to ensure the battery’s longevity and prevent dangerous situations such as emitting toxic fumes, fire, or even an explosion.
Therefore, medical device suppliers such as Medtronic, Greatbatch, Quallion, and Boston Scientific afford batteries with over-discharge (zero-volt) protection functions , , , .