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Not sure for LiIon batteries.

However, back in the days of NiCad batteries, some formulations could cope with really fast charges - and in fact would behave better and last longer after a very fast charge than they would after a slow charge.

We're talking about shoving 20 amps into a C cell for five minutes here. You needed to carefully monitor the cell temperature - the charging process wouldn't generate much heat until the cell was nearly full, at which point nearly all the energy going in would convert to heat. 20 amps would heat a full C cell up very quickly indeed.