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Energy storage solutions?

  1. Jan 12, 2015 #1
    Any ideas about how to get normal size rechargeable batteries that would last longer than 1 year (at least 3-4 years of 24h use) 5 to 15 volts
    I thought of http://en.wikipedia.org/wiki/Flow_battery but can they be that small and recharged fast enough ( at least a little faster than they discharge)
    There's also fly wheel but I can't imagine it in C,d or AA size
     
  2. jcsd
  3. Jan 12, 2015 #2

    Bystander

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    Spend enormous sums of money. Can you elaborate a bit on your requirements?
     
  4. Jan 12, 2015 #3
    I need a rechargeable battery of a normal battery size that can be charged faster than it discharges and that could last 3 years at least (in a condition of 24h use (charged discharged))
    I'm working on a device with a built in source of power, the device needs this source of power to work and the source of power needs the device to work but the source of power starts after the device after a delay of few seconds so my solution is to add 2 batteries. That's why I need 2 rechargeable longlasting batteries one will feed the device and the other will be charged by the source of energy. The problem is that they need to charge faster than they discharge and be long-lasting.
     
    Last edited: Jan 12, 2015
  5. Jan 12, 2015 #4

    Bystander

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    And you want something like AAA, AA, C, or D? Can't use small lead-acid batteries? Or modify something from a cordless screwdriver? Some of those are about the size of a roll of lifesavers.

    @Bandersnatch @phinds
     
  6. Jan 12, 2015 #5
    Thank you for your replies, I really appreciate your help
    I couldn't find any battery that would respect all of my 3 conditions
    1 Small size
    2 Charging faster than discharging
    3 Lasting for at least 3 years (knowing that it will be used 24/24h)
    I would be very thankful if you could give me some links to the solutions that you propose, I'm in Poland so I need to see where I could find it's equivalent.
    It doesn't even have to be a battery, just something that would help me with my delay problem
     
  7. Jan 12, 2015 #6

    Doug Huffman

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    See BatteryUniversity.com I don't see your capacity requirements. The lifespan limits of LiPo and Pb-acid are similar, roughly 3 - 5 years and 300 - 500 equivalent charge/discharge cycles.
     
  8. Jan 12, 2015 #7
    Thank you.
    Thank you for your reply, I greatly appreciate your help
     
  9. Jan 12, 2015 #8

    phinds

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    Like Doug, I don't see your requirements. "charges faster than discharges" is utterly meaningless since you have given no idication of HOW LONG it takes to discharge. If it is only supplying a trivial amount of current, it could take many months to discharge. Normal charge time is several hours.
     
  10. Jan 12, 2015 #9
    It must be continuous 5 to 15 volts (something in this order, the exact number doesn't really matter as I can adjust the device for that), longer it will take to discharge better
     
  11. Jan 12, 2015 #10

    phinds

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    OK, I'll assume 5 to 15 volts and no current at all, so the discharge time will be the lifetime of the battery which is several years. If you actually want to use it to DO something, the current will be more than zero and the discharge time will go do accordingly, and you'll have to SAY what the current load is. THAT is the "requirement" that I was obviously looking for. The voltage is pretty much irrelevant.
     
  12. Jan 12, 2015 #11

    DrClaude

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    In other words, how many ampere-hour do you need?
     
  13. Jan 12, 2015 #12
    20 amp-hour probably less
    I can make it work even at 5amps but 20 would be perfect
     
  14. Jan 12, 2015 #13

    Bystander

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    In WHAT size package? That's not a storage battery --- that's a bomb.
     
  15. Jan 12, 2015 #14
    sorry typo read again
     
  16. Jan 12, 2015 #15

    Bystander

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    From mortar round to hand grenade. You can't do with an amp-hr? That's about the capacity you can get in C and D cell size packages.
     
  17. Jan 12, 2015 #16
    1amp-hr ? as I said I can adjust the device, now it needs 5-20 but I can replace some parts of it, if I really need to
    but I need to know exactly what kind of battery I will use to find the appropriate parts, for now I'm just testing and prospecting
     
  18. Jan 12, 2015 #17

    berkeman

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    A 20 A-hr battery discharging over 1 year gives you about 2mA continuous. Is that enough for your low-power device to work on?
     
  19. Jan 12, 2015 #18

    phinds

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    I worry that if you don't even understand what the right questions are, enough to just get on Google and find the answers, that you are getting into something that is over your head and you need to study some basic electronics before moving forward.
     
  20. Jan 12, 2015 #19
    Wow, what's going on with people? all of a sudden they start aggressing you for no reason.
    try to think for 1 sec, if googling was enough and it was so easy to find, would I ask you?
     
  21. Jan 12, 2015 #20
    As I said, "for now I'm just testing" I will replace the current parts once I'll "know exactly what kind of battery I will use to find the appropriate parts, "
     
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