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Plug In Concept

Discussion in 'Gen 3 Prius Main Forum' started by Alexzan, Jul 5, 2022.

  1. Alexzan

    Alexzan New Member

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    Vehicle:
    2012 Prius v wagon
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    Four
    I have a 2012 Prius V, but posted here since this is not specific to Prius V.

    I am thinking of building a lifepo4 battery pack with its own BMS, and matching the pack so that the prius HV max voltage (I think 245v) is just 80-90% of the lifepo4 pack.

    That way when I connect them in parallel, and plug in charge, ill set the charger to the charge profile of the Prius HV battery, and when it is 100%, it will be about 80-90% of the lifepo4 pack. The prius can also regen into both packs this way.

    The first question is: Can the prius be programmed to drive electric only passed 40kmh? (Mine has a 40kmh limit for electric only).

    I did some calculations:

    prime range: 8.8kwh gets 40km : v size maybe: 35km.

    goal:200km, 50kwh needed.

    HV battery cut off voltage: 245V

    lifepo4 cell profile: 2.5-3.65, 93% soc = ~3.4v

    245/3.4v = 72 cells.

    72/4 = s18. or 4x s18 lifepo4 packs.

    50kwh / 4 = 12.5kwh needed per pack.

    245 / 50kwh = 200 AH lifepo4 cell needed.

    230AH lifepo4 cell = 4.5kg, 72 * 4.5 = 325kg.



    Looks doable? the bms can be 200 amps to support fast charging, higher discharge for the motor (if thats even a thing)?
     
    #1 Alexzan, Jul 5, 2022
    bisco likes this.
  2. PriusCamper

    PriusCamper Senior Member

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    Definitely doable!!!

    Except someone else has been designing & testing this exact same thing for 7+ years... And if you use my affiliate link to buy one you can have unlimited tech support from me: https://projectlithium.com/?ref=9qLPw
     
    #2 PriusCamper, Jul 6, 2022
  3. bisco

    bisco cookie crumbler

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    Plug-in Base
    i hate to be negative, but even when something is doable, it isn't always worth the effort.

    and most get bogged down and give up eventually.

    especially if they depend on others to provide help, when no one else has done it either.

    it's tough being a pioneer.

    what is very doable is cleaning the egr circuit before the head gasket blows :)
     
    #3 bisco, Jul 6, 2022
  4. ToyXW

    ToyXW Active Member

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    ----USA----
    Enginer (not engineer) and Hymotion (now A123 systems) made PHEV conversion kits for the gen2 and gen3, but demand plummeted when Toyota introduced the plug-in Prius (and later Prius Prime). Search priuschat because there were some issues users had go work out for themselves, especially with the enginer kits. That said, I think you can still get parts and very limited support for both kits (Enginer's website is still active and last year I looked at buying a government auction gen2 prius with a hymotion kit and confirmed with the US A123 distributor that I could still get parts for it).

    I also see a few PHEV kits in Europe (e.g. Pistokehybridi ). As far as I know, none were specifically made for the Prius V, but I know people were DIY adapting them to the highlander hybrid so I'm sure its possible for the V with enough effort.

    As far as I know, these kits did not increase the EV-only speed - that is a hardware limit of your transmission (technically motor generator RPM limit of the "power split device"). But at higher speed they could essentially make the engine idle and let the battery handle most of the power demand.

    I know you love to pimp your affiliate links whenever possible, but that isn't a plug-in conversion kit, just a replacement battery pack.
     
    #4 ToyXW, Jul 6, 2022
    Alexzan likes this.
  5. PriusCamper

    PriusCamper Senior Member

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    Yes, but if you bought a Prius with a Hymotion kit and swapped out the modules with a couple project lithium packs you'd have the best of both worlds. Of course LiFePo4 doesn't tolerate overcharging as well as NiMH so you'd have to figure out some type of early shut off just before full charge.

    Also I've found that the extra amps in a Project Lithium give you a few extra mph in full EV mode for some reason. Not sure why though?
     
    #5 PriusCamper, Jul 6, 2022
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