This evening I read with some surprise that the cousin of the 2400c, the 3400c, can use and charge the battery from a PB 190/ 5300, which is, of course, a NiMh battery rather than the 3400c's native Lithium Ion.

The 2400c and the 3400c are very similar machines technologically.... I am now wondering whether a 2400c would accept NiMh cells also. Could I damage the machine by trying? Or merely catch it, me and the house afire?

Mind you, cramming enough NiMh cells into the space occupied by the six Lithium Ion cells (presumably wired in series) would be a challenge, to say the least.