There are some vendors of li-ion rechargeable batteries that claim "drop in" replacement for lead-acid storage, without needing to update the chargers.
I have my doubnts, but I've run across stranger things [a].
They market them for such things as UPS'es giving you the choice of a lighter assembly or.. more time.
My specific application is... a rechargeable lawn mower. It currently uses 4 of the rectangular 12 volt batteries wired in series (not sure of the amp-hour rating), thus giving 48 volt DC.
The charger is a not-too-dumb one that draws 60 watts from the wall until it detects "something" in regards to the battery charge state (in quotes because I don't know if it's looking at voltage or something more impressive) and then cuts down to a couple of watts.
The mower, thanks in large part to the batteries, is pretty heavy (I have serious mobiity issues). I'd love to cut ten or even 20 pounds off its weight. (I'm quite satisfied with the run time - it's longer than, so to speak, my own run time...)
The vendors claim I can just drop in their packs and things should work. They're more expensive than the lead acid, but managable.
Any one have any words of wisdom? Thanks muchly
[a] we had 180 watt mercury vapor lamps (plus the 20 watt ballast) for outdoor lighting. Somehow or other somebody put together a fluorescent retrofit that simply screwed in and used about 40 watts (don't know how that affected the ballast waste).My head hurts thinking about the waveforms there..
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