Wheelchair/Scooter battery advice

[sqbr]

My battery has started running out AGAIN only a few months after getting it replaced last time. Anyone else had this problem? Is it plausibly just the price I pay for living on top of a really big hill? And if you live in Perth, where do you get yours replaced? I've been using Scooters Australia, which costs about $600 ie RATHER MORE than I'd like to be spending every few months /o\

Have been recharging whenever I'm not using it, trying not to let it run down too low when I'm out, and trying to keep the wheels inflated though we did forget about that for a while. And it's still run out faster than it did before I started doing any of those things.

Comments

[(Anonymous)]

had problems with mine recently and when i got it replaced the guy at the shop told me it was because i'd basically used a crappy off-brand battery as a replacement. i got it at a battery store that said it would work fine, but i guess that brand isn't designed for use in that kind of medical equipment or something. of course, then the one that guy told me to get instead that he said is better costs more, but he said it wouldn't die as soon like that. i don't know if it'll continue being true because i haven't had the new ones long enough, but maybe that is the case.

[sqbr]

Hmm! I got mine done by a dedicated wheelchair/scooter repair company, so you'd assume they'd use the right bateries, but maybe not...
Thanks for the input, anyway!

[jesse_the_k]

I'm so sorry you're dealing with this: scooter pneumonia is no fun.

The surface you travel on has the most impact:
loose sand -- most resistance, uses most power
packed sand
small gravel
large gravel
wood chips
shag carpet
cut carpet
asphalt
concrete
woodblock floor
woodstrip floor
tile, lino, vinyl
marble -- least resistance, uses least power

In my daily wander, I often travel 4km on concrete pavement. But going maybe just 1km in a hotel can drain my battery as much. (Well, that assumes that my battery charge meter is accurate.) Hills definitely make a difference: when I visited San Francisco I took a noonday nap to top up my energy and recharge my chair. In the flat midwest I can go all day. Some mobility devices let you install a range of batteries, from least powerful & lightest, to most powerful & heaviest. When you're traveling overland, the most powerful make sense, and that's always the ones I've gone with: Group 24, deep cycle, 52 lbs. Ugh—almost half my chair weight is the batteries.

Temperature does affect battery life: in my experience, when temps are over 30°C or below 0°C I get much less distance/charge.

I've spent the extra (US$750) for MK Ultra batteries, which claim to be made special for wheelchairs. The two times I didn't, I purchased "deep cycle marine batteries" of the correct size (so they fit) and electrical qualities (so they worked); they didn't last as long. The "deep cycle" bit is crucial, since mobility device batteries are often charged and recharged, and often at different rates—one day I'll go 30 meters, then next I'll go 5 km. In my town we have little-box, nothing-but-battery stores: they didn't have the right kind but they would have been happy to sell us the wrong kind. I am super lucky that MyGuy is an engineer who worked at a battery manufacturer for five years, so I was thrilled to let him make sure the specs were correct when he went to the farm supply store to buy the times we didn't do MK.

Mark Smith's Battery FAQs may be helpful, providing some background on the purpose of all the battery jargon.

There used to be an unbiased "all about batteries" site hosted by an electrical engineer with a mission to educate, but I can't find it now. The "Thomas Directories" collate corporation info about manufacturers of everything and anything—pre-web they supplied architects and engineers with a catalog 9 feet long. Here's their battery data but it's US, I'm afraid.

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Finally, it's possible that another element in your electrical system is letting you down and draining the battery even when you're asleep. Is the charger built in? It may have broken; try to charge with an external charger. Are the cords and jacks which connect the battery to the charging jack, then the charger to the wall, all solid, no breaks? If you have a lighting system, are all the connections there OK? Mark Smith, again, on Checking the Connections.

Best wishes!

[sqbr]

Thanks heaps this is all fantastic.