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  1. Voltage too high for Motor

    Electric Motors
    So I am currently looking for batteries for my conversion build at the moment and I have been looking into Lg Chem. They seem like a good choice but my only concern is that my motor, ADC FB1-4001, is rated for 120V. If I connected the Lg Chem in in series I would get 128V which is a bit over the...
  2. What motor voltage should I look for?

    Electric Motors
    Hello! I'm looking for electric motors for my EV conversion, and I've realized that I'm horribly under-informed... I have no idea what I should be looking for, especially in terms of voltage. I've heard that I should look for something between 100-200 lbs, and that I should be looking at...
  3. Voltage for 100-kW axial flux motor?

    Electric Motors
    Hi Everybody, For the development of a new motor which delivers 100-kW peak for a weight of 8 kg (185mm diameter axial flux motor), we are considering different choices for voltage / rpm. As you know, voltage relates to rpm and this motor will deliver 100-kW peak (50-kW nominal) at 12.000...
  4. Regen Confusion

    Batteries and Charging
    I have a 96 v dc agm pack, solitron jr controller, advanced DC brushed motor rated @120v. sports car (Lotus). I would like to add regen braking. But, newbie question: The motor spins backward to become a generator during braking? Managed by the controller. I don't understand the physics --...
  5. Voltage sag circuit

    Technical Discussion
    I found while driving my own EV that, if I hold the accelerator down too long, the motor draws a lot of current and the battery voltage sags low. The car simply will not go any faster under these conditions but, if I lift my lead foot off of the pedal for one second, the voltage lifts, the motor...
  6. Technical questions about engines

    Technical Discussion
    Hi, I have two technical questions about engines: The first is about power , I know that all electric motors gives maximum power as soon as you start , I mean a 500w motor will try to give it maximum output power from the beginning not as fuel engines right? And also they try to spin at their...
  7. Reading a Volt Gauge

    Technical Discussion
    Hi guys, I have my car running now (finally) and currently just have a multi meter for instrumentation. I'm running 96V which fully charged is around 104.5V. How do I convert a voltage reading to know what it means in terms of 3/4 charge, 1/2 charge etc?
  8. Low cost cell voltage monitoring development

    Batteries and Charging
    Low cost parametric cell monitoring development update. I have been developing an idea on how to make a low cost cell monitoring system. I would like to share some of my design requirements and progress to see if the product might meet the needs and desires of others. I am only at the...
  9. Lithium Voltage Sag

    Batteries and Charging
    Our 48 Thundersky LiFePO4 100Ah batteries have a top charge of 162 but sag while conservatively driving to around 124 or so. Is this acceptable, or harmful to the pack?
  10. Voltage Multipliers to achieve high battery pack voltages

    Technical Discussion
    Has anyone tried using a voltage multiplier, boost regulator or charge pump to get to the high voltages required to run some industrial motors? Mine requires a nominal of 600V, and I'm working on a boost regulator that can boost from a 120VDC battery pack to a voltage of 600 to 700 volts.
  11. manzanita shocker!

    Batteries and Charging
    So I'm charging my truck, main disconnect is off, and I'm going to start wrenching on the HV wiring going from the Curtis 1231C to the main disconnect. Just for fun, I decided to see if there is any voltage differential between what I'm working on and the trucks ground by using the wrench. A few...
  12. What to use from a forklift

    All EV Conversions and Builds
    Hi, If I can find the right forklift, Im thinking I can use the following.... 1) The batteries 2) The controller 3) The accelerator 4) A motor (I believe some lift motors are bigger than traction motors?) If the forklift was a 72volt, for example, am I right in thinking I can just add...
  13. Thundersky 160AH charging

    Batteries and Charging
    Hey, Just bought 46 Thundersky 160 AH's and did an initial charge in parallel with a small (5A) hobbie charger. Charged them several times and got a finished voltage of 3.4. Now the batteries are in my truck and I have gone 60 miles (30 charge then 30 more) with them. I'm charging them with...
  14. Battery voltage and discharging

    Batteries and Charging
    Hi, I am trying to judge state of charge for a my lifepo(TS90Ah,38 cells, ~120vpack) batteries and looking at the graphs from thundersky I am having issues.... I basically want to know the top voltage (100% charged) and the bottom voltage (70% discharge) range for the 90Ah units. The...
  15. Mythbusters: Higher voltage motor = more powerful motor

    Electric Motors
    I guess this question is part theoretical, part practical. Can anyone explain what the limiting factor is in the power any given motor can produce? Looking at the basic P=IR statement, I suppose with the same current flowing, higher voltage would produce more power. But then there's the...
  16. 96 volt pack to a 90 volt system?

    Electric Motors
    hey there this is my first post. I found a 1991 colenta pick up, here in holland, the pack is 15 x 6volt/160Ah, 90 volt agm and it is sulfated. I need new batteries and began to think of a lithium conversion. The closest pack voltage i can find is 96 volt. Would the extra 6 volt difference fry...
  17. EV Album Voltage versus Top Speed

    New Member Introductions
    I was curious about the practical relationship between voltage and top speed but I didn't know how to test it, everyone usually says voltage = top speed but can you draw something more concrete than that? Then I realised that the EV album has the voltage and speed data for a whole bunch of...