Converting to Lithium need Help

Discussion in 'Electric Bicycles' started by r731509, Jul 8, 2012.

  1. r731509

    r731509 New Member

    I have the 36 volt ebike designed by Lee Iacocca. I need a new battery but I am getting mixed information on what direction to go and how much to spend. There's a guy telling me he has the original battery and case that goes with the bike and that for this bike that is the best option a lead acid battery 36v 10ah. Another bike shop is telling my he can covert me to lithium and that he can customize the battery to fit in the original compartment on the bike at 36v 15ah but that will cost me $750 with installation. I guess my question is, is that price reasonable and if not where can I purchase a good battery to fit that compartment at the best price.

  2. sunworksco

    sunworksco New Member

  3. wheelbender6

    wheelbender6 Well-Known Member

    I almost bought an Iacocca ebike a few years back. I stuck with gas.
    Lipo batteries are lighter and can go 3 years before replacement. SLAs last a year or so.
    Lipo batteries can be almost completely discharged without damaging the batteries.
    SLA batteries suffer damage when discharged below 50% of capacity.
    Lipo batteries can sometimes be recharged in 3 or 4 hours.
    SLA batteries take all night to recharge.
    Lipo batteries require an extra controller, called a BMS.
    SLA batteries require no BMS and are usually easier to wire.
    --As you can see, there is no clear cut answer. You get what you pay for.
    If you commute over five miles without pedaling between recharges, I would spend the money for Lipo.
    Do a little reading on before spending the big bucks.
  4. sunworksco

    sunworksco New Member

    LiFe battery packs have more advantages over LiPo, except a bit heavier than LiPo.
    But unlike LiPo, LiFePO4 cells (3.3V/cell) can be an excellent replacement for NiMH on voltage basis. And compared to high-capacity NiMH packs, the Hyperion G3 LifePO4 have these other advantages:
    More capacity per gram, meaning longer duration between charges
    Almost no "self discharge", so your ready to go even weeks after charging.
    Faster charge time
  5. pedalman

    pedalman Member

    For my 45V, 500W direct-drive setup I went with 4 of these:

    Turnigy 5000mAh 4S1P 14.8v 20C hardcase pack

    Last edited: Jul 24, 2012
  6. sunworksco

    sunworksco New Member

    New Lipo Technology

    MIT and other universities in America have just proven a new anode/cathode technology that uses silicon sponge instead of cobalt. It will be a real EV battery changer. It has proven to give tens times the power density of current lipos and can charge/discharge in under five minutes. Internal combustion engines are going to take the same path as steam and become obsolete. Even Ferrari has an EV/Hybrid and it is faster than the ICE version of the line without the engine on.
  7. bluegoatwoods

    bluegoatwoods Well-Known Member

    I'm not an expert in this area, but I've read a lot from folks who know on

    The only thing that I feel I ought to comment on here is the question of safely charging. You'll hear people say that you have to watch the lithium type batteries like a hawk (and having the local fire dept standing by ain't a bad idea either). You'll hear others say that it's all a bunch of hooey and that they're just as safe as SLAs.

    But one guy who seems pretty trustworthy to me says, "If you want to plug 'em in and go to bed, then these aren't the batteries for you'. (Though, to be fair, he doesn't seem to regard them as unsafe, but merely needing close attention.)

    Me? I like to plug them in (outdoors unless it's just too cold) and go to bed.

    So I'm gonna stick with the SLAs for a while.
  8. sunworksco

    sunworksco New Member

    Best to use a Duo battery charger by Hyperion.
    It has individual battery cell balancers and also an optional temperature sensor. Another trick is to keep the batteries in a crock pot when charging. This assures that nothing will catch on fire. Lipo batteries burn very similar to a hydrogen flame, directly upwards like a torch. Always have a fire extinguisher handy, as well. You can charge them in your garage. They only take a few minutes to charge, with the correct charging system. I use LiFe and Lipo batteries often and the Lipo are the lightest and fastest charging.

  9. pedalman

    pedalman Member

    Energy density of lithium ion batteries is like 15x that of lead-acid batteries and lighter, not to mention lead-acid batteries are not made for continuois discharge really as needed in an ebike.

    Wouldn't charge them in a garage...plenty garages burned down as mentioned in some RC forums((Radio Control people use these apparently,not Duracell"s)...Outside somewhere would be safer.(unless of course you watch them like a hawk)
  10. pedalman

    pedalman Member

    I'm pretty sure you can't go below 3.5V per cell, complete discharge is a no-no.
  11. schulze 123

    schulze 123 Member

    This is correct, in the model aircraft game we try to not go below 3.2V per cell or 20% of cell capacity. Operation below this will harm the cells, so to will leaving them at low voltage/capacity for a long time. a storage charge of 50-60% capacity is a good idea ifthe packs are not going to be used for a period of time.

    Cheers BJ
  12. pedalman

    pedalman Member

    How do you know if you are about to go below 3.2V while flying the model aircraft?
  13. schulze 123

    schulze 123 Member

    Hi Pedalman,
    The speed controllers that we use have programable low voltage cut off. Example 32 volts for a 3.2 volts per cell on a 10s LiPo pack. Some of the contollers have a lead to attach to the balance plug on the pack to read the voltage of each cell in the pack. This way if any cell goes below the programmed voltage, the motor will be shut down. Some manuacturers have this feature available as an add on device.

    Cheers BJ
  14. pedalman

    pedalman Member

    Thanks BJ from down under, you got me thinking, my bike kit controller(48V,500W) that came with the kit from yescomusa might have something like this built-in, yet ppl on ES recommend low-voltage alarms for the battery. Kit supplied controller has no specs, don't even know what company manufactored it,probably better safe than sorry.