That's a tricky one. The job of actually installing the new battery packs is something I'm going to get the dealer to do, being the local outfit that supplied the mower. Coxy has a computer interface plug that (after battery replacement, I suppose) is hooked up to the dealer's computer running Husqvarna software called autocheck. A number of usage counter values and other recorded details are read from Coxy, into the dealer's computer, then appropriate values in Coxy are reset to zero. Not something that the home handyman can do, obviosly. Like certain other e-devices on the market, there is the possibility that non-OEM battery packs would lack a certain chip and so be rejected by either Coxy's on-board micro-processor or the dealer's software module.
Even if I tried to do it myself, I would not be able to do what the dealer's software can. There would be no warranty problem with me attempting the task, as the guarantee expired, a year ago. The OEM pack is Li-ion. There are a range of 'knock-offs' available at much lower prices (half), but they are NiMH, not Li-ion.
I have done cordless drill battery pack replacements, myself, so have a small idea of what's involved. That aside, I think it's better to give the local dealer the job. I've had good service from them, since day one, too.
I'm now on the way to arranging the purchase of replacement battery packs from Germany. I have located a shop there where they speak fair English and give the impression of being quite good at what they do.
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