I have a Livarno Lux (Lidl) cordless spotlight - the sort with a large diameter lens at the front, behind which is a powerful halolgen (55w) bulb and a ring of LEDs, and with a white LED and flashing red LED at the back.
It normally travels in the boot of my car in case of emergency, but tends to roll around a bit - which may be related to the problem.
I recently found that it was completely dead - none of its 4 lights would work. [You're supposed to charge it regularly since the battery can apparently be damaged if it becomes deeply discharged. It was working when I tested it 3 or 4 weeks ago, so it's possible that it got turned on while rolling around (don't we all!) and flattened its battery.]
I recharged it for over 24 hours, and the battery's open circuit voltage is well above its rated 6v. Three of the 4 lights now work, but the 55w halogen doesn't. I've tested the bulb on a bench power supply, and it lights up ok - but in the lantern, nothing. It's drawing several amps but not lighting - or even getting warm, so I don't know where the energy is going.
55w at 6v equates to over 9amps, so the filament resistance is only about 2/3 of an ohm when hot - even lower when cold. Any additional resistance in the circuit will have a dramatic effect on the current, and probably stop it lighting.Question to those who are knowledgeable about rechargeable batteries . . . What sort of "damage" is likely to result from being discharged too deeply? Is it possible that this could increase its internal resistance? If so, is there any remedy - or is it scrap?