If you put 240v straight into a Lithium Ion 8.4v (and not through the charger)light will it be completey knackered or not?

Cheers

Try using the battery and see?

It’s not likely to do it much good, but it depends on how long it was plugged in. Fraction of a second, might get away with it, more – probably damaged it. But Lithium Ions have a tendency to get flamey when upset, so you may be lucky.

It’s not working, but I was wondering if it needs charging “properly”??!!

I wouldn’t, next time it could do this take care kids!

it will most likely have blown the protection circuit .

so the cells may be ok give old smudge a call he is will say if it can be mended.