Dead lithium battery testing
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Discussion

Wreckerd

Original Poster:

73 posts

127 months

Friday 29th May 2020
quotequote all
My mums mobility scooters battery is dead.
(It has 4 battery lights on it indicating charge level, none are on. )
It’s a 36v lithium pack.
She’s broken the charger, I can’t find one for less than £400 which is a bit expensive, especially if it turns out the battery is dead also.
The broken power supply is 42v 4amp. There are also extra wires on the charger, I assume they’re for temperature monitoring of the battery during charging.

How dangerous would it be to use the nearest battery charger I’ve got (a 30v 2a one) and try to charge it for 5 minutes at most, just to see if it’s going to hold a charge? I’d do it outside obviously, with the bare battery on the ground.
Any ideas welcome.
Full spec
36 V / 3.4 Ah / 122 Wh Lithium ion battery.

Wreckerd

Original Poster:

73 posts

127 months

Friday 29th May 2020
quotequote all
If I could get 1 light to light up on the battery I’d be happy enough to buy a new charger. I’m not intending to charge it more than 5 minutes.

cml24

1,591 posts

177 months

Friday 29th May 2020
quotequote all
Are you able to check the current battery voltage? If its only sat at say 30V at present then the battery charger won't do anything anyway.


cml24

1,591 posts

177 months

Friday 29th May 2020
quotequote all
Might be worth getting in touch with someone like mtbbatteries.co.uk and see if they can help on either checking the battery, building a new one or even supplying a charger.

Dogwatch

6,384 posts

252 months

Friday 29th May 2020
quotequote all
How on earth do you break a battery charger?

As said, a 36v battery won't take much notice of a 30v charger. Weakling!