What type of battery should I choose?

Discussion in 'Power Electronics' started by Rafa Sperati, Jul 15, 2016.

  1. Rafa Sperati

    Thread Starter New Member

    Jul 15, 2016
    Hello! my name is Rafael Sperati and I'm from Brazil.

    I'm working on a project to record videos of a Roller Coaster ride.

    I have it all done but the last part that is the power supply.

    I must feed a 12v / 11w camera for up to 10 hours, and I also need the battery to support the trepidation, turning around, shaking coming from the Roller Coaster and be the smaller as it can be. I'm thinking about buy a 14ah Battery, this way it will never get full discharged.

    So the real question is: What type of battery should I choose?

    - 14 ah or more;
    - Supports turning around, shaking, vibrations;
    - Smaller as it can be.
  2. MaxHeadRoom


    Jul 18, 2013
    LiPo are pretty small for their capacity.
    What is the physical limits you are looking for?
  3. Rafa Sperati

    Thread Starter New Member

    Jul 15, 2016
    I don't have specified physical limits determined, You must imagine that its going to be flying upon peoples heads and amusement parks have solid security rules, so this way I must appear with somenting discrete.

    I'm not sure about using LiPo batteries, I read about the explosion risks, and they are too expensive.

    I was thinking about someting like this LiFePO4 battery:

    But I never used this type of battery, and I don't know if its going to support being discharged and charged everyday.
  4. ian field

    AAC Fanatic!

    Oct 27, 2012
    Lithium is going to be the smallest and lightest, you can purchase a charger that automatically balances the cells for best possible safety.

    Its pretty much a consequence of lithium cells having such high energy density - if something does go wrong; its a lot of energy escapes in a small space.

    A second choice would be Ni-Cd - they're getting harder to come by because of the toxicity of cadmium. Ni-Mh have at least 2x the mAh capacity per cell size, but higher internal resistance - they can't handle high current draw.

    SLA batteries are tried and trusted, but bulky and heavy. They are easily ruined if left discharged for any length of time.
  5. Dr.killjoy

    Well-Known Member

    Apr 28, 2013
    What about using 18650 cells or similar ??
  6. Rafa Sperati

    Thread Starter New Member

    Jul 15, 2016
    Hello guys! after researching a lot I decided to use a LiFePO4 Battery. They are extremely small and light and support more charging cycles. They are expensive but at the end it worth because of their lifetime.

    In this case I choose a LiFePO4 Sports Motorcycle Battery to support all the vibrations coming from the Roller Coaster.

  7. ian field

    AAC Fanatic!

    Oct 27, 2012
    Most modern motorcycles don't vibrate any worse than most cars, but the battery is probably a pretty good choice.

    You could buy individual cells and design the mounting/packaging to withstand high levels of vibration for lower cost - the important thing is to buy a charger that automatically balances series cells.
  8. BobTPH

    Senior Member

    Jun 5, 2013
    This part worries me a bit. How heavy is the battery? Do you expect it to be included on the unit attached to the head? Given the forces involved, keeping it on would be a real challenge. If I were running the roller coaster there is no way I would allow it.

  9. Rafa Sperati

    Thread Starter New Member

    Jul 15, 2016
    Well I changed my project camera to a less consumption one, this way I can use a 7ah Battery. I choose a Aliant YLP07 Battery, that gives me 2 years of Warranty.
    This battery dimensions are 114mm x 40mm x 98mm, very small for a 7ah, and weights 450g, thats pretty good.

    Remembering that this Battery is design for sports, like extreme enduro.

    What you guys think about this battery?