On 20 Feb,
Ian Jackson wrote:

There's no way that a 500mA wall wart could ever deliver enough current
to kill a car battery.

The important thing would be to check what the charging current actually
was (flat battery and full battery), and see if there was enough / not
too little to be of use / not too much so that it would kill the wall
wart.

I recently killed a battery by substituting an AC wall wart for the genuine
article. Another family member had shuffled the warts and I didn't spot it in
time. I now attempt to label all warts with their original use. It may save
other expensive mistakes.

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