Short-Circuit Protection for 3-6 Volts AA Batteries

[Rod_learning]

I’m looking for a circuit that can protect 3-6 Volts AA Batteries when a short-circuit happens. When the short-circuit happens, a second circuit (LED blinking) must be triggered and the batteries must be protected. The goal is that the LED won’t stop blinking until the short-circuit is undone. Could someone give me hand at selecting cheap suitable options for this application? E-fuse, p-channel mosfet, x2 transistor arrange, Ideal diodes, a Battery protector CI? The only requirement is that the circuit also operates when two 3Volts AA batteries are connected in series.

 

[KMoffett]

Please post your circuit that the batteries are connected to.

 

[Pommie]

How are shorted batteries able to light an LED?

Mike.

 

[Visitor]

Are the batteries powering the detection circuit separate from the batteries to be monitored?

 

[gophert]

How are shorted batteries able to light an LED?

Mike.

Are you saying that shorted batteries are somehow in a "protected" state as the OP stipulated? I don't think a shorted battery is in a protected state. Shorting is very damaging to batteries.

 

[gophert]

Here is a latching comparitor circuit with design help from TI. You'll have to sneak the LED light into the tripped circuit bit should be straightforward. The "sense" resistor is quite small in this one and can be a challenge to work with such small values because solder joints and PCB traces can be a non-insignificant percent of this value with a significant impact on accuracy. With this model design, you can redesign with a higher value sense resistor.

https://www.ti.com/lit/an/snoaa39/snoaa39.pdf?ts=1601211602933&ref_url=https%253A%252F%252Fwww.google.com%252F

 

[picbits]

Use a self resetting PTC type fuse with a flashing LED in parallel with it. When batteries are shorted, the PTC will mostly become open circuit and the LED across it will blink.