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Rate of discharge for a battery

  1. Apr 7, 2010 #1
    I am designing an electric vehicle and choosing the batteries. For this i want to model some inefficiencys into the batteries. I came across the formulae T=C/I^n where

    T=battery life
    C = capacitence
    I= current
    n= Peukert's number

    would 1.1 for n be ok for lithium ion, it seems to take quite a lot off with large currents, i couldnt find a general number for li-on only that lead acid use 1.2-1.3.....

    Battery = 100 Ah
    Voltage motor = 156 v
    cell voltage = 3.3v
    average current = 36 Amps

    the current was calulated from power requirements at any given time P=IV
    Last edited: Apr 7, 2010
  2. jcsd
  3. Apr 7, 2010 #2


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    Gold Member

    C is not capacitance, it is battery capacity. Re n, I don't know but a good Li-ion should be much less than 1.1.
  4. Apr 8, 2010 #3
    Actually from reading the wiki on this it looks like the equation is meant for lead acid only, so probaly thats why i cant find a number. I would like to find a general alogorithm just to make things simpler in my spreadsheet!
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