BMS Design Considerations

Thread Starter

arman74

Joined Jul 1, 2017
37
Hey guys .I have a 50 cell li ion pack and i need to control the important li ion parameters such as temp. over current short cir. and etc. I have placed a low side n channel mosfet to break the circuit in case of short circuit and a 1mohm resistor to sense the current and a simple noninverting oppamp to measure current. My circuit breaker works fine but in case of short circuit it is kind of slow and the mosfet explodes before getting off.
1575782149083.png
When current goes up the voltage across the u1 goes up and after it goes more than the negative pin of u2 the oppamp will change from low to high and it generate an interrupt on the mcu and mcu turns off the mosfet. Mosfet gate is driven by the schematics below:
1575782708231.png
 
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