My camera lithium ion got locked out...any fix?

I have a digital camera that runs on a rectangular prismatic battery. The battery got discharged too far (in one time, not over storage) and dipped below the cut off voltage.

The OEM battery will cut off the output once below the threshold voltage, but reactivates the battery when charged.

This Lenmar got locked out and won't reactivate.

What now?

Contact the place you got the battery and ask if that is the intended effect? If not, ask if will they replace it.

Actually I may not be the LVC. Most likely the terminals were shorted
on accident and an over current protection tripped (not all reset).
One way to know is to measure the terminals. If there is no V at all
then you've tripped the overcurrent protection. If there is some V
below 2.6 then you may be right either way, you're toast unless you
replace the pcb inside the pack. Check ebay. There probably are some
third party li-ion packs for your camera.

sysadmn said:

Contact the place you got the battery and ask if that is the intended effect? If not, ask if will they replace it.

Click to expand...

I asked for an RMA number. They said they're sending me a new one and didn't even ask to have the old one back.

This makes me wonder if this has gotten so common with their products they just don't bother to get the old ones back.

The battery has three terminals

-, T and + and a thermistor between - and T. It reads 3.6v under no load, but instantly collapses with the slightest load. I think the circuit shut down the connection between - and battery and the 3.6v is through the thermistor resistance.

I know the terminals weren't shorted. It sat in my camera for a long time and completely discharged. Applying 4.2v, it accepts no current betwen - and +.

The OEM original will shut off output to 0.0v on over discharge, but applying charge resets the circuit. Not on this generic.

My fix involves a hammer & a solid surface.

Dr Jekell said:

My fix involves a hammer & a solid surface.

Click to expand...

That would be appropriate for certain flashlights, but not for battery under warranty.

And especially not appropriate if the battery is a Li-ion!
You might get a bigger bang than you expected!

For some battery (both Li-ion and Ni-MH) low voltage lockout, the protection circuit can be unlocked :

1. Charge it with small current by a DC power supply (or DC adaptor) in series with a proper resistor to limit the current to around 10mA.

2. Example, use a 5-6V supply (or just the USB port), and a 200-500ohm resistor to charge the battery (Li-ion or Ni-MH) for more than 10 sec.

3. This should able to unlock the protection circuit.

4. My La Crosse BC-900 refuse to charge Ni-MH with voltage <0.5V. This method work very well.

As Ni-MH cell does not have protection circuit. The lockout here on Ni-MH means too-low cell voltage for charger to recognise the existance of the cell.