Looking for ideas on how to charge my power chair in a survival situation

Discussion in 'Power Electronics' started by hotwheels, Feb 17, 2017.

  1. hotwheels

    Thread Starter New Member

    Feb 17, 2017
    9
    0
    I am a complete novice when it comes to circuits. I want to learn but at the moment my knowledge is very limited. I am physically disabled.I have very limited use of hands and arm and I use a power chair. I know enough about survival to know that during a bug out one is only as good as one's feet or in my case my chair. So, I need to find a lightweight way to charge my chair off the grid. A friend suggested a Tesla circuit, but I researched that a bit and I now feel my friend is not well informed. I live in Sunny So Cal, so, I have thought of solar panels but they would be hard to attach to my chair.

    the chair works on 2 24 volt 8 amp batteries. Any ideas that do not have a high potential of killing me would be helpful. Thank you
     
  2. DickCappels

    Moderator

    Aug 21, 2008
    4,863
    1,470
    It might be helpful for us to know the capacity of your batteries.

    Solar cells might seem attractive because they are clean and quiet but the power output per square meter might be too low to be practical for your application.

    Chemical energy sources such as gasoline can deliver a lot of energy per unit weight and volume. Maybe a small gasoline or diesel generator connected to a battery charger will end up being the best solution.
     
  3. crutschow

    Expert

    Mar 14, 2008
    19,518
    5,443
    I think Dick has a good solution.
    A small, gasoline or propane powered generator should readily charge your batteries.
    Propane fuel has the advantage of being easy to store and having a very long storage life as compared to gasoline.

    Do you know how much power the battery charger requires and how long it takes to charge the batteries?

    Even in sunny SoCal there can be several days in a row without sunlight. ;)
     
  4. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    9,632
    1,103
    Would a genset be lighter than a spare set of batteries ?
     
  5. dl324

    AAC Fanatic!

    Mar 30, 2015
    6,944
    1,606
    Welcome to AAC!
    Is your intent to charge the batteries while you're on the move or to charge when you're stationary?

    If stationary, the panels don't need to be connected to your chair. But charging would still be slow...

    How long do you anticipate needing to charge your batteries? If it's long term, you need something that doesn't require fuel; e.g. a crank generator that can be powered by wind, water, or hand. Unless you plan to make your own fuel using wood (woodgas).
     
  6. crutschow

    Expert

    Mar 14, 2008
    19,518
    5,443
    So how many spares would he need?
    And how much of a pain is it to change the batteries?
     
  7. crutschow

    Expert

    Mar 14, 2008
    19,518
    5,443
    The generator also has the advantage of being able to power other devices in your home, such as the refrigerator, etc.

    Edit: If you can afford it, the inverter type generators output a lower distortion and stable voltage waveform for powering electronic devices.
    They also allow the generator to operate at a slower speed for light loads, minimizing noise.
    But they cost more, so that's the tradeoff.
     
    Last edited: Feb 18, 2017
  8. KeepItSimpleStupid

    Distinguished Member

    Mar 4, 2014
    2,772
    492
  9. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    9,632
    1,103
    Automatic Battery change over
     
  10. KeepItSimpleStupid

    Distinguished Member

    Mar 4, 2014
    2,772
    492
    A lot of UPSs will do the transfer from line to battery, but won't start if told to on the fly. Warning - some UPS's are not compatible with generators.
     
  11. spinnaker

    AAC Fanatic!

    Oct 29, 2009
    6,644
    2,928

    My eyesight is bad. I need to use my glasses and that always has worried me in the event of an emergency. My problems are minor by comparison to yours.

    Do you have the use of your legs? Maybe a pedal powered generator?

    [​IMG]


    Or maybe simply a recumbent trike? Do you have use of your arms enough to steer? If not I think you can get them where both steering and brakes are operated by your feet and legs.
     
  12. hotwheels

    Thread Starter New Member

    Feb 17, 2017
    9
    0
    Thanks everyone:
    I really don't know how much power the charger needs. I know I plug it in overnight and it charges the chair to full in like 8 hours or so. My concern with a spare set of batteries is A. knowing how to connect them ( easily fixable I can learn) but the weight is the bigger concern. I have more use of arms than legs as far as petaling things. I thought 24 volt 8mp was the capcity of the batteries. If it's not, how do I find this info out? I have used a hand trike before... as far as how long I would need to be off the grid I will have to do a bit of looking on the survival side to see what experts reccommend but I would think it's best to be ready for a month or 2 at least.
     
  13. crutschow

    Expert

    Mar 14, 2008
    19,518
    5,443
    Why the talk of UPSs? :confused:
    He just wants a way to charge his power chair battery when the mains are dead.
     
  14. hotwheels

    Thread Starter New Member

    Feb 17, 2017
    9
    0
    crutschow yep and if i can find a way that will fit in the ILBE ( military backpack) that i got to use as a bug out bag all the better. That is my big concern being left in a danger zone after everyone bugs out. If TSHTF rural areas may be safest and offer the best resources for a while.
     
  15. hotwheels

    Thread Starter New Member

    Feb 17, 2017
    9
    0
    I just realized that what may have to happen is have one thing that is bug out ready ( fairly light and portable) and another or plans for another for set up whereever the bugout leads to. the chair or I should say a new chair with new batteries can go 30 miles on a charge. So, I typically charge it once a week.

    The reason I thought of putting the solar pannels on the chair is because I am concerned about having to move a long way, but even in this context I would not necersarily need to charge while moving.
     
  16. KeepItSimpleStupid

    Distinguished Member

    Mar 4, 2014
    2,772
    492
    Hey, it's "an option", but not necessarily the right one. I don't, in general make choices, but rather create options. They could very well be bad options, but I won;t make that judgment.

    Part is, the power went out at home and I have to change the power chair, but it doesn't look like that's what we are dealing with. Earlier in the thread, no indication of time.

    A UPS keeps batteries charged. I think on my UPS, it can be turned off, but can keep the batteries topped. So, if you need power, you can "turn-on" the UPS on demand and use whatever AC charger you normally use. Lifetime may be crappy, but it's still an option and probably a bad one as details emerge.

    --

    Batteries have a "capacity".
    "mp" is not a capacity. 8 Amp-hours would be a capacity. 8 Amp-hrs is the same as 8000 mA-hrs. This means it is supposed to be able deliver 8 amps for an hour. It's really just a way of comparing batteries and comparing costs. So, 8 amps for an hour or 4 amps for 2 hours. etc. The 30 hr life of the chair per charge is more complicated.
     
  17. dl324

    AAC Fanatic!

    Mar 30, 2015
    6,944
    1,606
    Googled and found this combo hand crank generator and solar panel setup.
    https://www.amazon.com/Military-Generator-Charger-Converter-Notebook/dp/B01N3LSX0W

    It's going to be pretty tough being a survivalist in a power chair. Have you thought of a buddy system?
     
  18. hotwheels

    Thread Starter New Member

    Feb 17, 2017
    9
    0
    Sheltering in place is less of a concern because I can move around my home by crawling if need be. when the chair breaks I typically have to live a week or 2 without my chair but a bug out means getting out of the city to where water and other things are more readily available. Cars may not be useable as roads can be blocked or unsafe. So one needs to be prepared to walk or its equalvalent. I have no intention of being left in the city to wait until there is no water in the tanks. I am memorizing survival info so that what I know may motivate those around me to bring me with them even if it is a pain in the rear.
     
  19. hotwheels

    Thread Starter New Member

    Feb 17, 2017
    9
    0
    thanks for the link. By the way, if anyone with the knoweldge wants to work with me on designing a power chair that is survival ready please let me know ( if we can get a man on the moon, then surely it's possible to build what I have in mind... something with wheels like a tank that charges on solar during the day with back up batteries for night time. It would probably be possible to get corparate sponsors ( put ads on any open spaces on the first batch just to get things off the ground. My grandpa worked on engineerung for apollo I wish he was still around. Anyway, power chairs sell for a lot. And no chairs meant to help disabled people live through a bug out exsist ( i have looked and looked) . The designers of such a chair could clean up big time.
     
  20. dl324

    AAC Fanatic!

    Mar 30, 2015
    6,944
    1,606
    I remember seeing a tracked power chair that could negotiate stairs. But power efficiency wasn't a design constraint.
     
Loading...