Fig. 1 is a block diagram of circuitry in a typical Li-ion battery pack. It shows an example of a safety protection circuit for the Li-ion cells and a gas gauge (capacity measuring device). The safety circuitry includes a Li-ion protector that controls back-to-back FET switches. These switches can be
Protection Circuits are crucial components in a BMS, safeguarding Li-ion batteries from potential risks such as overcharge, over-discharge, and short circuits. These protection circuits monitor and prevent overcharging, a condition that can lead to thermal runaway and damage. They may include voltage limiters and disconnect switches.
When a short circuit condition occurs the current draw is way higher than the maximum rated current of the battery pack. This condition can affect the cell’s health or even cause damage to the cell leading to fires. This is also why there is an overcurrent and short circuit protection built into the chip.
The protection features available in the Battery Management System are listed below. When a lithium battery is charged beyond a safe charging voltage, the cell heats up extremely and its health is affected and its life cycle and current carrying capacity get reduced.
In our testing, the cell voltage gets as low as 2.7V for each cell, and then the protection features kicked in and cut the output. Overcurrent protection in a BMS is necessary to safeguard the battery from high current load or short circuit conditions.
Battery protection circuits / IC solutions and reference designs that allow easy design-in and ensure safe charging and discharging - prevent damage and failures.