Cheap 24VDC Battery Tender?

[Wildchild467]

I was looking on surpluscenter.com and came across this battery charger for lawnmowers. Its 24VDC, would this be a cheap alternative to a battery tender? It only puts out 32 watts, which is only .75 amps. That would be good enough to keep batterys charged up in the winter months. I know it would take forever to charge the batterys up if they were down, but just a trickle to keep them warm. For under $10, seems like its worth a try.

https://www.surpluscenter.com/item.asp?UID=2384021215323729&item=11-3150&catname=electric

 

[markmontana]

Will you put a couple simple clamps on the battery end of the cable?

 

[armytruck63]

I have a 24 volt charger for an electric wheelchair. It makes a great 24 volt trickle charger. When I get home, I will try to get the manufacturer and model number.

 

[70deuce]

Here's report on this unit. I bought two of these $8.95 24 volt battery chargers or maintainers as I use them. Very happy with them. After sitting for a month, on the M818 with two large 8D batteries with 1155 cranking amps each, the unit brought the static voltage up from 23.7 volts to 26.9 overnight. Voltage stayed above 25 for almost a week after disconnecting the unit. It appears they will work very well as a maintainer. Probably not a charger for MV's but works good to keep the batteries up for a strong start next time you need to go cruising. They come with a 1/8" round female plug which I cut off and soldered color coded alligator clips to. I checked the link wildchild467 posted above and it shows hundreds still available.

 

[steelypip]

Rated output is 32W @ 24V, which is about 1.3 amps. Great for charging a motorcycle or lawn tractor battery string, great for charging up smallish gel-cells (which is what it's for). Probably would keep 4TLs or 6TLs topped up OK, but you'd die of old age waiting for them to charge up - assuming 50% charge efficiency and an 80% charged 6TL you're talking about a 40 hour charge time.

But it should do just great as a maintainer, especially if you put it on a timer (see my other post).

I'll be getting one of these - just exactly what I want for the two garden tractor battery solution I have in mind for the MEP-002A.

Incidentally, they show 14 available right now...

 

[TexAndy]

Here's report on this unit. I bought two of these $8.95 24 volt battery chargers or maintainers as I use them. Very happy with them. After sitting for a month, on the M818 with two large 8D batteries with 1155 cranking amps each, the unit brought the static voltage up from 23.7 volts to 26.9 overnight. Voltage stayed above 25 for almost a week after disconnecting the unit. It appears they will work very well as a maintainer. Probably not a charger for MV's but works good to keep the batteries up for a strong start next time you need to go cruising. They come with a 1/8" round female plug which I cut off and soldered color coded alligator clips to. I checked the link wildchild467 posted above and it shows hundreds still available.

If you just immediately checked voltage after taking the batts off the charger, that was probably surface charge.

To get a more accurate reading, measure voltage after it's been off the charger a few hours.

 

[BIG_RED]

In his defense, he did say "It stayed over 25 volts for a week" - so it did do SOME charging. I agree that you'd be waiting forever to actually charge a large battery with that thing, but 1.3 amps would be a good battery maintainer - nice find.

 

[70deuce]

My two large 8D batteries did in fact stay above 25 volts for some time. Again this unit is not going charge 24 volt batteries as used in MVs. As used by me the unit did a good job of maintaining the charge even during the cold periods of Colorado winters. Just a note, after driving the truck for sometime I would put the unit back on the batteries and it showed it was charging (red light) for a few hours and then go green. So it brought whatever charge level that was on the batteries after driving the truck up to a higher level. Bottom line the unit works for me as a maintainer.

 

[bones1]

Good information, I have just started looking for a good 24v maintainer. The wheelchair chargers look interesting as well.

 

[jimmcld]

I have the wheelchair charger. I figure I can always use it for my wheelchair when I get too old to drive my MV. Actually, it will charge four dead 6tl's overnight.

 

[goldwing2000]

Good find. The shipping to me is 50% more than the charger.

 

[steelypip]

The only hazard for me is going to a site like surplucenter. I was a very good boy this time and escaped for less than $50 all up, which just means I gritted my teeth and said 'no - can't afford that' a lot. As it is, I did pick up a battery disconnect and some other good things for the generator install project.

 

[TexAndy]

The only hazard for me is going to a site like surplucenter. I was a very good boy this time and escaped for less than $50 all up, which just means I gritted my teeth and said 'no - can't afford that' a lot. As it is, I did pick up a battery disconnect and some other good things for the generator install project.

I bought all my sprockets, chains, shaft collars, large bearings, etc... to automate a dillon 1050 with an old lifestyler treadmill.

I'm a BIG fan of surpluscenter. Their prices are excellent.

 

[Gunner0311]

I just ordered one. S&H cost more than the charger! Oh Well....

 

[bones1]

Any more info on wheelchair chargers?.

 

[goldwing2000]

Any more info on wheelchair chargers?.

I've been checking them out and I don't see why they wouldn't work. Most have three wires instead of 2, so the third is probably just a voltage sensing lead to tell it when to stop charging. They're also only about $6.

 

[armytruck63]

Here's what I have. It's for a 24 Volt electric bicycle, not a wheel chair like I earlier said. I don't know how much this costs as it was given to me by my dad. I usually hook it up to the deuce if I haven't driven it for a while.

 

[Smokinyoda]

How about something like a scooter charger? I found a 12v 2amp modle for $11.99 shipped on ebay. Or would a 1.5 amp charger be a better maintainer for our purpose?

2 amp - 24 Volt Battery Charger for Schwinn & Mongoose Scooter | eBay

1.5 amp - New 24 Volt Charger for Schwinn & Mongoose Scooter 24V | eBay

These are not my auctions, and there are multiples available so saw no harm in posting links. If its a problem I will delete them.