I’d go even lower, maybe 50mA. The main issue you’re fighting is internal resistance, which will cause things to heat up. Your other issue is that I’ve averaged things, however it’s quite likely that one or more cells has a significantly lower voltage than others (and therefore a higher resistance) so can cause more risk.

If you’re able to get the pack apart and measure the cells separately that will help a lot

Yes

I am assuming that 18v is 5 cells in series, with a nominal voltage of 3.7 x 5 = 18.5 volts. At 15.22 each cell is around 3 volts. 3 volts is usually considered the absolute minimum you can discharge cells to. (3.3v is considered flat) If it won’t charge, it’s probably dead.

It might be possible to rig up a charger to very very slowly charge the battery up to about 3.3 volts, at which point the proper charger might agree to fully charge the battery, but with the cells already below 3.3v there’s a good chance it won’t work even if you did that. And it’s not without risks.

Yep, in the exact same was as blockchain: nowhere.

They allow non-folding bikes off-peak in non-tunnel sections or on newer trains (like the Elizabeth line). They allow folding bikes at any time anywhere.

Sadly yeah. Hence “was” ☹️

AbiWord was probably the closest as a FLOSS equivalent?

And I hope they can’t sell them because nobody actually wants to buy one.