Ride-on Toy Batteries

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I have a small 40 watt BSP pv with battery and controller that lights led lights in the basement utility room. I would like to use some of the power for a couple of led reading lights elsewhere in the house but the cable runs are prohibitively long. I have a couple of 12AH 12v gel batteries from my kid's old electric ride-on toys (brand is peg perego) and am wondering about charging these every week or so and using them for remote voltage sources. The led reading lights will only draw about 300ma each.

Would it be better to parallel the small batteries to the main battery for the charge or would I just plug the charge transformer into my small emergency inverter that I have attached to my controller?

Anybody ever done this?

Thanks

66merc

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,491 admin
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    Re: Ride-on Toy Batteries

    I would suggest looking at NiCAD or NiMH batteries... They are much more rugged for this type of application. Just use a 12 volt DC adapter for a bunch of AA batteries.

    Lead Acid batteries tend to sulfate if they get more than a day or three on them if stored/operated at less than ~75% State of Charge.

    If you already have the battery--then you will want to charge it correctly... I would be wary of just connecting it to the main battery bus--Ideally, using a real battery charger would be safer and better for the battery. And, I have had very poor luck with the Wall Wart type of charger charging the batteries (typically way overcharge). You should watch the battery on a wall charger--or I have also put them on a lamp timer and set it to turn off after 6 hours--or whatever your need--so that I don't have to worry about forgetting to unplug the charger.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
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    Re: Ride-on Toy Batteries

    I would agree with Bill to use AA cells. I have a baby monitor that runs off 12v, so I use 10 AA's. It will run for 3 weeks until the AA’s die, but I change the batteries every week. I have two other "led night lights" and even a cordless phone base I do the same thing with. I use 3 MAHA 401 charger's that ran from my 12v battery bank, no AC involved.
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • System2
    System2 Posts: 6,290 admin
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    Re: Ride-on Toy Batteries

    Thanks for the replies.

    OK, a quick search brings up lots of NiMH shrunk wrapped battery packs. If I bought one of these battery packs, would I have to have a charge controller? It seems a pain to charge ten batteries separately. Or expensive to buy three battery chargers. Anybody suggest a decent, cheap charger for a 12v NiMH pack?

    Also
    what could I do with these little gel batteries? Seems like a waste not to use them and 12AH could be useful in some little way.

    66merc
  • BB.
    BB. Super Moderators, Administrators Posts: 33,491 admin
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    Re: Ride-on Toy Batteries

    If you need NiMH AA or AAA batteries for devices that take a week to a year to use up all of the power... Look for "hybrid" NiMH batteries.

    Sanyo Eneloop is one very good brand, somebody else (RayoVac or other large battery company) also makes Hybrid NiMH that have a good reputation.

    The Hybrid NiMH are designed to hold 80% of their charge after one year, most standard hi-capacity NiMH, after a few months or so of use, can loose most of their charge in one month.

    So even though the hybrids are slightly smaller (maybe ~2,000 mAhrs vs ~2,500+ mAhrs), if the batteries are used for more than a few days between recharging--the hybrids will last longer than the standard NiMH.

    If you have access to a Costco in your area--they sell the Sanyo's for arpoximately $26 (8xAA + 4xAAA + 1 four cell smart 6 hour slow charger--apparently a one time deal for Costco--when gone, there will be no more--my Costco's don't have anymore). They also sell (IIRC) for $18 a pack of 6xAA + 2xAAA Sanyo's...

    For battery chargers, you can get slow "smart" chargers (roughly 6 hours), fast chargers (roughly 1 hour) and extremely fast chargers (roughly 15 minutes). The 6 hour and 1 hour chargers are more or less standard smart chargers. The 15 minute chargers may be a bit hard on the cells--but many people use them just fine.

    Which chargers... Boy, that is a rough one to summarize... Basically, you want to find a charger that as independent channels for each battery (i.e., 4 channels = 4 batteries, each channel can charge a "different" battery--charge level, brand, capacity). You usually want to avoid a charger that forces you to charge in pairs or such).

    Maha makes very good chargers (from what I have read). A few to look at:

    Maha MH C401FS (4 channel AA/AAA)
    Maha C9000 (four channel, highly user programmable)
    Maha MH C808M (8 channel AA/AAA/C/D NiMH/NiCad) Detailed Review

    To look for anything battery related (typically AAA through D and lithium chemistries--usually something you can stuff into a flashlight) go here CandlePowerForums/batteries-included (I don't think you need to register to read the forums--I have been there for years and zero junk mail)

    -Bill

    PS: By the way, Amazon.com is supposed to have some good deals on occasion. Also, look at http://thomasdistributing.com for some of the Maha (and other) chargers. -BB
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
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    Re: Ride-on Toy Batteries

    I guess if you really want to use up those small 12v cells you could do the same sort of thing with them, charge them in parallel with you solar battery and then move them to where ever and use them. I you can string even a small wire between the main battery and the remote one it should work at the smaller levels your talking about. It usually not a good idea to mix old/new/different batteries but it sounds like they are extras so it might not matter.

    When I first started down the NiMH AA path I used to think it would be a problem but not I just keep a dish of charged ones and uncharged ones. So I might grab 10 out of the charged bowl and drop the 10 in the uncharged bowl. Then as I remember I put them in the chargers. I haven’t had an issue with it.

    As Bill noted the Enloops are my favorite, they really hold up well over time and perform well under load as well, very predictable. But for our kids toys I went with less expensive Tenergy batteries from
    http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=848
    I bought 60 on sale from them with free shipping for $45 about 4 months ago and use them in the kids toys guilt free. I did come across 3 duds so far, while haven’t found a dud eneloop, I use those in my real flashlights or electronics.
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
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    Re: Ride-on Toy Batteries

    if the led lights are setup already for 12v operations then go with using them and charging up those gel batteries from your pv through a small controller or use a regulated car battery charger to charge them up with.
  • System2
    System2 Posts: 6,290 admin
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    Re: Ride-on Toy Batteries

    Thanks again for the replies.

    I like the Tenergy site, Brock, but I'm still wondering how you are using ten AA at a time? Do you have some sort of plastic pack to stuff all of them into?

    66merc
  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
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    Re: Ride-on Toy Batteries

    I use a pack holder that holds 10 AA's and has a 9v snap connector on it for 12v items. It makes it easy to change out and I just make an adapter from 9v snap to what ever fits it. They make them in 10, 8, 6, 4, 2 and 1 cell holders like these

    http://www.batteryholders.com/aa_6to10.shtml

    The ones I use are all the 4x4 or 5x5 size back to back, pretty small
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI