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Gen 3 Performance Battery Upgrade

Discussion in 'Gen 3 Prius Technical Discussion' started by NoInstructions, Dec 7, 2019.

  1. NoInstructions

    NoInstructions Junior Member

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    I was looking for ways to boost the performance of a gen 3 Prius, and it seems nobody has tried increasing the power output of the hybrid battery.

    There seem to be quite a few people trying different performance upgrades (Turbo, Nitrous, etc), to a Prius, but none of them seem to have much success. Has anyone tried this with a Gen 3?

    The closest thing I can find is @TMR-JWAP who put gen 4 cells in a gen 2 Prius. Since the newer cells have higher max power output, He was able to get more power from the car, and a 0-60 time of 8.5 seconds. If you can do this with a Gen 2, and it doesn't even require doing anything to fool the computer, why not do something Simular with a Gen3?

    According to the gen 3 specs, MG2 in the gen3 has a max power of 80hp. With the traction battery's max power of 36 hp, most of the time the remaining power is generated by MG1 by the engine, which makes it more efficient, but means the engine is contributing less mechanical power to the wheels. Theoretically, one could upgrade the hybrid battery power up to 80hp, which would allow MG2 to operate at 100% power without any electricity generated by the engine. This would translate to either 80 hp in pure ev mode, or 178hp in full power mode. A prius with 178 hp.

    The best part is MG2 is Already producing 80 hp in some situations, it's designed to do this. This would also have very little impact on mpg, even possibly increase it in the city, and would only require an upgrade of the battery and perhaps the wires running to the motor. Is there something I am missing about the system? Is there any reason this is not doable?
     
  2. Elektroingenieur

    Elektroingenieur Senior Member

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    Yes, the software in the power management control ECU (HV CPU), which determines the target motive force, and how much power and torque to demand from the engine and motor-generators. See the Hybrid Control System section of New Car Features (more info), and specifically the diagram “Flow of Motive Force Calculation.”

    Even if the HV battery could support a higher discharge rate, it’s unlikely that the hybrid system would take advantage of it without modifying the software, which as far as I know, has not been reverse engineered sufficiently to allow changes to such fundamental operating characteristics.
     
  3. Grit

    Grit Senior Member

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    If it does sustain high discharge rate, the heat build up would be rapid in need of a louder rpm fan to cool the HV bat. The part that op left out is ICE would spend more time charging the HV bat due to high discharge spiraling mpgs down.
     
  4. NoInstructions

    NoInstructions Junior Member

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    I've looked into this more, and have also realized that even though the inverter is rated for 80hp, the 650v DC-DC converter certainly isn't. seems like the only option would be to hack a converter out of another prius, and combine it with the current converter, definitely not an easy task.

    As far as changing software, there's no need to if you can trick the car on a hardware level. In this post: 1nz-fe Cam Swap | PriusChat Toyota Jesus tried adding current shunts around the current sensors, so the ECU sees less current. since his only issue was the breaker on the battery tripping, an upgrade to the battery would fix this.

    I'm not sure I'd do this to my car if I had the money though, considering all the inverter failure issues in the gen 3.
    Instead, I'm looking into doing a camshaft swap on the gen 3 prius.
     
  5. GG707

    GG707 Member

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    One way I believe that might be to spoof the dcl with a unit to go between the bat unit and the motor ecu... The discharge current limit in mine was 28-30 and now does not go more than. 22 in any case... After an update at Toyota dealler regarding the inverter's reliability and long life blah blah blah.. so if we could some how decode the part of dcl a s allow the inverter pull more current than 35 kw (assume it can withstand it... ) The car might be a 0-100 in less than 10s ... As it used to be when the limit was 30kw...

    Posted via the PriusChat mobile app.
     
    #5 GG707, May 25, 2020
    Last edited: May 25, 2020
  6. AzusaPrius

    AzusaPrius Senior Member

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    Bumblebee has a beefed up battery version called BeeMax.

    Oh Im gonna say this now before I get called out for working for Bumblebee. I do not and I am just a consumer.

    Posted via the PriusChat mobile app.
     
    bisco likes this.
  7. bisco

    bisco cookie crumbler

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    or just buy a car with the performance you're looking for
     
    //go_prius_2 likes this.
  8. NoInstructions

    NoInstructions Junior Member

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    Yeah, that's the logical thing to do, isn't it? I like the challenge of trying to improve the Prius, though. :D

    If there was a faster, efficient car that can get 40mph, has the same amount of cargo space, and can be purchased for around 5-6k, I might trade for that. But, the Prius does have some great perks, like being able to run the accessories and AC without the engine on, and it's extremely reliable.
     
    Threej and bisco like this.