Maintaining batteries on old chair

[john66]

I assuming I don’t disconnect the batteries, how often should I charge the batteries on my old chair to best maintain them?

[Burgerman]

overnight every 2 weeks max. At float only if possible. So 27.2V.

[john66]

What do these two things mean. Sorry for my ignorance. Thanks.

"At float only if possible. So 27.2V."

[Burgerman]

I mean that...

If the chair was previously fuuly charged, and as sat for 2 weeks then its now at 99% ish. Does that mattery? Yes. Because that 1% missing is 1% of the capacity that is now lead sulfate coating the plates. If you leave it that way it turns to larger xstals, that dont conduct so will forever stay that way. And your battery now has 1% less Ah.

So That this doesent happen, and so this doesent end up at 2%, 20% or worse, we need to return that sulfate back to the electrolyte where it came from while its possible.

Since the battery is nearly full, a high rate recharge that wwe use in cyclic daily operation isnt required. Just 16 to 20 hours at a high float level such as 13.6V. Or 27.2 for a pair.

With the XXD thats easy. Just set it to POWER SUPPLY and choose 27.2V. Start it, go to bed. Take it off in the morning. Or dinner. Not critical.
No elevated "fast charge" at a higher voltage is needed.

Or set to LEAD CHARGE, and choose 27.2V. And choose say 0.4A, and then float at 27.0V. Set 5 hours float. And Auto off.

[john66]

There are no settings on my charger. I just plug it in and that’s all. Below is a picture of my charger. Does it charge with a float like you describe and it won’t overcharge the batteries? Thanks.

[Burgerman]

Those things do all kinds of things. Never tested 2 that did the same thing. Every one was abysmal, innacurate and over voltaed and undercharged. Then they generally go to a too high 13.8V (27.6v) float.

If I used one of those and I wouldnt, I would charge a nominally full battery for 8 hours. And hope for the best... Every 2 weeks.

Heres a wildly spiky graph, that was MONITORED by the PL8 hobby charger, so we could see what one of those chargers actuually does. And I still am not sure!

By a user on here.
This one was supplied by invacare.

[john66]

I got my new quantum chair and it came with this charger that is available on Amazon.. Is it any better than the other charger I showed above.?

https://www.amazon.com/DA200U-250A-R-Ba ... B0BZDSR32P

[Burgerman]

Not really. Never tested one. And theres no proper spec. But...
Any charger that has AGM or GEL on it without any way to switch it from one to the other will never charge either one properly. But thats the same with all mobility chargers. They all pretend they can charge both, and they all tell you its done long before it really is so that people dont complain when they cant charge it in that 8 hour overnight timespan.

So it is what it is I am afraid.

[Burgerman]

If you REALLY care about chargng properly are willing to learn and spend a little you need one of these...

But for just charging lead its a bit overkill

With this you get complete control. It can be a 2 stage charger, a power supply, a 3 stage charger, lithium and lead, and from 0V to 70V and 0 Amps to 50A. It can be used to test motors, electroplating, charging, or a general high powered bench supply.

Its a long way beyond what you would need. And not much difference in price...

[scottnj@gmail.com]

What is a good source for the ZXD?

[shirley_hkg]

Trump's administration taxes everything that went through their custom, especially from China.

[Burgerman]

Taxes and tarrifs from the UK to the US are 12.6%.

This calculator below allows you to enter CHARGER and its value (at which point you can be less than truthful!) and I put £200 uk pounds.

Which is about £200 is $269 dollars at todays rate. Total is $33 dollars tax/tarrif/duty. $303.00
You can also add your sending country and any receiving country. So I put UK to US. Theres no tarrifs or taxes on any shipping costs.
So its really pretty cheap. Maybe less than it was pre trade deal even with tarriffs added.

At least from Great Britain. Less than our VAT for e.g.

[shirley_hkg]

I'm surprised that he treats us so kind.

[Burgerman]

Its a deal or no deal thing!
HK is not China... Well not really, it was British.
But its not 4 dollars its 8. Because your 1200 HK is about half the £200 UK value I used? (I think???) Still cheaper than here, just!