Charge my AA battery with Solar power? easy?

I was wondering if I wanted to charge my AA batteryies, about 2 of them. Is it as easy as plugging a solar panel, one that is getting about 2.1 volts, directly to the battery itself? Will that charge it, or do I need other stuff involved?

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Charge my AA battery with Solar power? easy?

    viruz5,

    Unfortunately, the answer is much more complicated...

    First, obviously, it matters on what the battery chemistry is--different chemistries have different charging requirements...

    Most common rechargeable AA's are NiCAD's and NiMH.

    And while NiCAD's are the most forgiving of rechargeables--can take discharges to zero volts and fast recharges very well--but is about 1/2 the capacity of a NiMH AA...

    NiMH are a bit less rugged vs NiCAD. And they are more difficult to "fast" recharge because, one a NiMH battery becomes fully charged, its voltage drops a tiny bit--and the chargers have to look for this voltage--which is difficult to detect--and have a backup protection to prevent damage (timer, over temperature detect, and such).

    So--to your question--Generally, recharging a NiMH or NiCAD at a rate of C/10 (10% of rated current, or 10+ hours to recharge)--just about anything you do will be fine... A simple solar panel that output 10/C amps at a voltage higher than the battery, with a blocking diode (to prevent discharging at night), will charge your battery just fine. That means with a simple solar panel--it will take 2 days or more (assuming around 5 hours of sun per day, summer and clear weather) to charge your cells.

    If you want to quick charge your batteries (C/5 to C/1 or less), you can get into an issue where you can overheat the cells and cause them to vent (or worse)... And a vented cell is usually damaged beyond use. Here you would need a true NiMH/NiCAD battery charger to safely top-off your batteries.

    In the end, I have not seen any good quality quick solar chargers for AA batteries... Most will take days (or in some cases weeks) to recharge a set of two or four batteries.

    You could get a fast charger (1 hour or so rated) with a 12 volt input (say a cigarette lighter) and connect it to a solar panel--but you would probably blow the charger as most "12 volt" solar panels output 17-21 volts.

    So, typically, a recommendation would be to make a solar+solar charge controller+12 volt storage battery set--And then use that system to plug in a 12 volt AA fast charger. And this gives you the advantage of charging at night, or charging more than one set of batteries quickly via the large storage battery + solar panels.

    But, of course, if this is for portable use--this would not be a small system to lug around.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?

    thomasdistributing.com used to carry some small, self contained, solar power AA & AAA battery chargers. None listed now. MOST of the "solar" chargers you find, take 2 full days to recharge AA batteries, and 1 day for AAA batteries. Many do NOT have a decent charge controller built in, and rely solely on the fact that they have such a wimpy solar panel, that they can not hurt the batteries until you leave them on for days and days.
    Mike

    PS I've done the large PV panel & 12V car cord for a respectable AA charger - I think it's the way to go.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • System2
    System2 Posts: 6,290 admin
    Re: Charge my AA battery with Solar power? easy?

    ok, thank you guys for the advice!
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?

    Just chargers, not Solar Chargers. I got a nifty one with a fair size panel, charges 5AA for a 5V USB power connector. Can use it to charge cell phone or any USB gadget.

    found this on Amazon: $25
    http://www.amazon.com/Solar-Folding-supply-battery-charger/dp/B000XD9O2E/ref=sr_1_5?ie=UTF8&s=sporting-goods&qid=1219985908&sr=8-5

    ""What you get: 6 volt, 200 mA folding solar panel"" (1.2Watt)
    So if you have 2,000ma AA batteries (4 in series ) it would take 10 hours of good sun, or about 1.5 days, to recharge the batteries.

    If you got a "real" (5 watt or larger) panel, it could charge a small 12V battery, and then any charger with a car adapter, could be used to charge the AA's

    http://store.solar-electric.com/1to39wasopa.html
    a small battery http://store.solar-electric.com/de8a34ampho1.html or a battery from a UPS or even a motorcycle battery could be made to work.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?

    you aren't really getting a charger with what you found mike, but you are getting a small solar panel. i see nowhere that it says it has any regulation circuits in it and rechargable batteries won't last as long without the regulation, especially nimh batteries. the chargers i point out have regulation circuits and any that have a wall wort type of ac adaptor to reduce to say 12vdc can have the small solar panel connected to it. odds are the small panel may not have enough power to run the charger properly so a bigger small panel may be needed. i'm not sure if preregulation may be needed on some of them or not for the high voltages of some panels can be problematic depending on the regulation circuits in the charger.
    bottom line here is that they don't make good aa/aaa solar chargers that i've seen yet.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?

    Here's my 64Watt Solar AA charger. Cost about $500 for all the parts, but it is very reliable, and can recharge AA's 24/7 running off the 12V storage battery.
    Pics 1 & 2 & link to construction hints
    http://www.ae-zone.org/Designs/monolith/monolith.html
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?

    Hi Mike, looking at the pics and your link I can not find a list of all the bits and pieces you have hooked up, other than the CC and Fluke meter and batt charger. could you itemize them? (Looks like a Serial hookup to ? from the black box [inverter ?] on the side.)

    Eric

    ps and something with a USB looking plugin...
    ej
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?
    westbranch wrote: »
    Hi Mike, looking at the pics and your link I can not find a list of all the bits and pieces you have hooked up, other than the CC and Fluke meter and batt charger. could you itemize them? (Looks like a Serial hookup to ? from the black box [inverter ?] on the side.)
    ps and something with a USB looking plugin...
    ej

    Construction: http://www.ae-zone.org/Designs/monolith/monolith.html
    Now linked to my facebook page, which is open access to this album:
    http://www.facebook.com/album.php?aid=2074858&id=1196643274&l=7e66e96c3c

    parts :
    Unisolar 64
    C-12 charge controller (nowdays I'd get a Morningstar SunSaver MPPT w/RTS)
    PepBoys 3 way cig lighter outlet
    Fuse
    Malibu Light wire (heavier than 18ga zip cord)
    MAHA MHC401FS 1,2,3 or 4 AA or AAA charger w/12V car cord
    http://thomasdistributing.com/shop/-maha-mhc401fsdc-battery-charger-black-model-aa-and-aaa-chargerbrincludes-100240v-ac-world-adapter-and-12v-dc-power-cordbrfree-deluxe-storage-bag-free-8-cell-battery-holder-case-p-821.html?SP_id=&osCsid=i8an56kre0b28ruqm66scfmj23
    Costco Deep cycle batterys (got 4 years of pretty heavy use out of them)
    PV panel charges 2 deep cycle batteries. 12V lighter plug powers most loads. A 300W pure sine inverter powered power tool chargers, ran tools all day, charged AA's for night lighting.
    Misc chargers and adapters for my Palm Treo phone.
    You can use any panel, just adjust the plywood cuts to fit the cabinet to the panel.

    Alos shown,(all black, w/USB slot) but no longer avaib, is a flip top, 2 PV's AA charger. Holds 5 AA's and has USB output for charging gadgets, or a USB keyboard gooseneck light
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?

    mike,
    i don't remember if you had said it before, but what is the weight of the complete charger?
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charge my AA battery with Solar power? easy?
    niel wrote: »
    mike,
    i don't remember if you had said it before, but what is the weight of the complete charger?

    Haven't a clue ! Takes 2 to carry, and if the 2 deep cycles are in it, you don't carry it, use a dolly. It's a full sheet of 5/8 plywood, lots of 1x2, and the PV itself, I'll guess empty (no batteries), it's about 40 lbs. With the hefty trunk handles I installed, 2 people can carry it with 1 battery in it. I move the whole thing myself, with a dolly. I can load it into my truck, lay it on it's back, on a 4" ABS pipe, and roll it into the cab-hi camper shell.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • rohanjcp
    rohanjcp Solar Expert Posts: 30 ✭✭
    Charge my AA battery with Solar power.
    mike90045 wrote: »
    Construction:
    Unisolar 64
    C-12 charge controller (nowdays I'd get a Morningstar SunSaver MPPT w/RTS)
    PepBoys 3 way cig lighter outlet
    Fuse
    Malibu Light wire (heavier than 18ga zip cord)
    MAHA MHC401FS 1,2,3 or 4 AA or AAA charger w/12V car cord
    Costco Deep cycle batterys (got 4 years of pretty heavy use out of them)
    PV panel charges 2 deep cycle batteries. 12V lighter plug powers most loads. A 300W pure sine inverter powered power tool chargers, ran tools all day, charged AA's for night lighting.
    Misc chargers and adapters for my Palm Treo phone.
    You can use any panel, just adjust the plywood cuts to fit the cabinet to the panel.

    Hello mike,
    I am very glad to see your project here online and with photograph. I was hoping to create a similar emergency charger backup power kit like yours, but simpler. I would start with a 65W Kyocera panel and would like your advice on the rest of the parts, if you were to do it all over again.

    You have been kind enough to answer to my post titled Emergency Power. However, I am a beginner and do not know about fuses and wires. All I know from my book on solar panels was that I do need to fuse close to the battery. Is this something that requires cutting wires and technical skills?

    Like you, I also own a MAHA MHC401FS with DC plugs. So I also am curious about how the PepBoys 3 way cig lighter outlet, Fuse, Malibu Light wire (heavier than 18ga zip cord) work together and where you got them. Do you have any suggestion where i can learn to recreate your setup step by step?


    Also, where can i get the item below?
    mike90045 wrote: »
    Also shown,(all black, w/USB slot) but no longer avaib, is a flip top, 2 PV's AA charger. Holds 5 AA's and has USB output for charging gadgets, or a USB keyboard gooseneck light

    Many thanks rohanjcp
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charge my AA battery with Solar power.

    > Also shown,(all black, w/USB slot) but no longer avaib,
    > is a flip top, 2 PV's AA charger.

    Means it's no longer sold anywhere.
    Fuse needs to be installed, you need to know how to splice wire, make connections, and know your right hand from your left, even when upside down.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,