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Prius LiON battery: Not the Prime but close enough

Discussion in 'Prime Technical Discussion' started by bwilson4web, Oct 23, 2017.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

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    2017 Prius Prime
    Model:
    Prime Plus
    I am amused:

    It appears the service plug has the full B+ and not via the current sensor. If you wanted to tap the battery, we'd need a negative socket-plug assembly.

    Bob Wilson
     
    #1 bwilson4web, Oct 23, 2017
    Last edited: Oct 23, 2017
  2. Andyprius1

    Andyprius1 Senior Member

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    Hi Bob, What is a negative socket-plu assembly?
     
  3. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
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    Location:
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    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    The battery has a negative and positive socket-plug. The safety plug is on the positive side of the battery and the battery control relays do not appear to be in series with the plug but follows. This means the safety plug is a direct, B+ tap point. This leaves the problem of getting a negative tap.

    If we could fabricate a socket-plug, T assembly, the battery negative could be tapped since it appears to be a direct connection to the battery modules, not isolated by the battery controller relay.

    My interest is how to access the Prius Prime battery without having to modify the case:
    • B+ - a modified safety plug
    • B- - a T adapter with a socket-and-plug to pass through to the car
    Several applications come to mind:
    1. 120VAC inverter power - it should easily handle 7kW with the right electronics
    2. Fast DC charger - with an appropriate adapter, CSS/CHAdeMO.
    3. 12VDC substitute - weighting less than a lead acid battery, significant reduction in weight
    Bob Wilson
     
    #3 bwilson4web, Nov 18, 2017
    Last edited: Nov 18, 2017
  4. Andyprius1

    Andyprius1 Senior Member

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    I see, I forgot that the car has something similar to a floating ground and one cannot simply connect from B+ to chassis ground, it’s a great safety feature. Now if you bypass that safety feature, would both contacts conduct, or would the reading be zero? As Patrick Wong explains it, ther are 3 relays, one for each bank and one that conducts to the inverter. Am I understanding correctly?