How to set up a safe lithium battery protection circuit Circuit Diagram This article discusses important safety and protection considerations when using a lithium battery, introduces some common battery protection ICs, and briefly outlines selection of important components in battery protection circuits. Overcharge. Lithium batteries can be safely charged to 4.1 V or 4.2 V/cell, but no higher.
Protection circuits for Li-ion packs are mandatory. (See BU-304b: Making Lithium-ion Safe) More information on why batteries fail, what the user can do when a battery overheats and simple guidelines using Lithium-ion Batteries are described in BU-304a: Safety Concerns with Li-ion. Intrinsically Safe Batteries
304: Why are Protection Circuits Needed? Circuit Diagram
Working of Li-ion and Li-Po battery discharge protection circuit : Please refer to the schematic in Figure 1 for the following discussion of the circuit's operation. When switch S1 is pressed, transistor Q2 is turned ON by R3 and R1 to ground. This applies the battery voltage to three branch circuits.
For instance, if you have a holder for 18650s and a protection circuit connected to it, it's a 50/50 chance that your circuit will power up once you insert the battery.
Lithium Ion Cell Protection Circuit Diagram
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 opened to protect the pack against fault conditions such as overvoltage, undervoltage
