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  1. T

    EMS motor controller connector identification

    I have a project that uses a motor drive kit from Electric Motor Sport. The CAN pins have been broken out to a 6-pin connector in one of the wire harnesses. I was hoping to reuse this connector but I can't identify it. Its 6-pin, but only two are used, its white plastic house, pins are male...
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    Fisker & Karma are getting along very well it seems...

    I can't believe people are actually buying these things. I think I could design and build a better car out of Legos.
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    Prismatic 20Ah A123 battery module CAN bus communication

    As stated above its standard CAN 2.0B. I've used A123 battery pack systems for a couple projects and never really had any issues talking with them, but I also have all the config files and Vector tools. Unless you have an excessive amount of time on your hands you're going to need the .dbc files...
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    Maximizing LiPo lifespan

    The SOC range of the cells as stated above is very important for range. You normally find a window between 20%-90% SOC on most high production EVs and around 30-80% SOC for hybrids that use Li batts. The smaller the window, the more cycles you can get from the battery. However, the smaller the...
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    Battery Connecting & Switch

    Don't put a switch in series with with your battery, it will only melt or generate losses due to added resistance. Are you sure about this? My battery charger gives very specific instructions on connecting the battery and it clearly states to plug in the charger in first and then the battery.
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    Cooling Polymer/Pouch Cells?

    All batteries are prone to thermal runaway, no matter what chemistry. The only advantage LiFe has is that its failure mode from such an event isn't catastrophic. The cells may be rated to 10-15C but that doesn't mean you can slap a bunch of them together in parallel and you're good to go. If the...
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    Cooling Polymer/Pouch Cells?

    Its not just cycle life you need to be concerned with if you're doing discharge rates as high as you stated. Internal impedance decreases with temperature which can promote thermal runaway if you have cells connected in parallel. If there is a large variance in temperature across your pack, its...
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    Cooling Polymer/Pouch Cells?

    I think 115F is pushing it a bit, unless you don't care about losing that 10% life. Most Li chemistries like to stay under 40F for best longevity and performance. Anyway, like mentioned above thermal management is often more about equal temperature distribution rather than keeping things cool...
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    Direct Methanol Fuel Cell technology-30th May

    Contrary to the thesis of the article, this is not a novel nor new technology. DMFC's have been around for a long time both in the lab and in the market place. In some applications you can make a good case to use DMFCs but for most you can't. There is also a rival technology, Direct BoroHydride...
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    PC Powersupply for Lipo Charger

    I've been using PC power supplies to run my chargers ever since I got into RC as a wee lad (about 10 years ago). I actually picked up some $20 POS supply yesterday to power my Cellpro 10S charger. Almost done modifying it. I've never really had a problem with supplies not hitting their rated...
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    LiPoly compression, how much?

    For those of you that are running LiPoly packs, or pouch cells in general, how much pressure are you putting cells? What are you using to allow expansion of the cells? I've finished the battery plates and hardware for my current ebike project but still need to order some springs but don't know...
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    How do you prevent your connectors from arcing?

    OK, so it looks like the simplest way to do it is the way I've already considered. Well, a pre-charge with a 100Ohms resistor it is then. Anyone tried using a big inductor in series with the battery? I thought about it for a second but figured that when cutting the throttle back there would...
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    How do you prevent your connectors from arcing?

    I'm currently working on my battery pack for my E-bike and of course the wires arc every time I connect the battery to the controller. Does anyone have any good solutions to stop this from happening? I was going to make a second set of connectors in series with a 100Ohm resistor to precharge the...
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    What kind of battery is everyone using?

    Thanks for the advice. I ended up going with lipo's from Hobby King even though I said I'd stay away from them (TopherTheME = Hypocrite). I'm going to be building a 36V 20AH pack since my charger only goes up to 10S. Later this year I'm going to try and get some of the A123 20AH or maybe a few...
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    What kind of battery is everyone using?

    All Lipo's have a relatively high impedance due to the components which make them Lipos. Because of this, they all have relatively steep discharge curves as neptronix pointed out. Yes, they almost never come with a BMS in hobby applications but thats to keep costs down, not because they don't...
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    What kind of battery is everyone using?

    Ok, I have to ask, why do lipo's not require a BMS? Sure you can run them without one but you're taking a hit on performance and longevity. What lipo packs do you have?
  17. T

    What kind of battery is everyone using?

    I'm just getting started into this whole Ebike thing and ordered a conversion kit from E-bikekit.com yesterday. I'll be turning my 10 year old mongoose into my daily commuter. I'm having a lot of trouble choosing a battery though. I see a lot of people using LiPoly batteries, which I have a lot...
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