1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Autocross Gen3, need a way to force charge

Discussion in 'Gen 3 Prius Technical Discussion' started by TheChip, Apr 24, 2017.

  1. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    Hey guys, I've searched and read previous threads about autocross and charging, but it doesnt seem to work for me. Putting it in drive, smashing the brakes hard and hitting the accelerator doesnt seem to charge the battery for me. It spools up the engine, but the lines move from the battery to the wheels, not the other way around. I don't want to break anything so I didn't try more than twice.

    Anyone have ideas on how to get a full battery charge? Doing an autocross run with a dead battery is going to be awful.
     
  2. RMB

    RMB Senior Member

    Joined:
    Jun 21, 2016
    406
    642
    0
    Location:
    Oakland, CA
    Vehicle:
    2014 Prius
    Model:
    Three
    Since it's been a couple days and no respond yet, I just throw in my 2 cents.

    I might have read from somewhere (really don't remember where though) pressing the brake and then throttle will rev up the ICE thus charging the traction battery. I could be wrong, and if I am, someone please correct me on this info.
     
  3. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,120
    10,047
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Did you also try this in Park?
     
  4. RMB

    RMB Senior Member

    Joined:
    Jun 21, 2016
    406
    642
    0
    Location:
    Oakland, CA
    Vehicle:
    2014 Prius
    Model:
    Three
    Oooppsss... forgot to include doing this in Park, not while the vehicle is moving.:ROFLMAO:
     
  5. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    11,491
    14,100
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius
    Model:
    Two
    To charge it up the quickest if it's healthy and you're just wanting max power for the competition, I'd recommend gentle to moderate acceleration and hard braking to pump it up, but don't brake so hard you use friction instead of regeneration. It'll take several repetitions. My gen 2 used to get full bars frequently with the stupidly timed traffic lights here.
     
  6. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    Hitting the throttle in park doesn't charge at all, no lines moving on energy monitor, I let it go for about 2 minutes like that with no change.

    Doing this in drive with the brakes on shows the battery charging but also the electric motor trying to work the wheels, also no charge.

    Maintenance mode sits with the engine on but no charging. :/
     
  7. RMB

    RMB Senior Member

    Joined:
    Jun 21, 2016
    406
    642
    0
    Location:
    Oakland, CA
    Vehicle:
    2014 Prius
    Model:
    Three

    uh..... Guess what I read or my memory is wrong, my BAD!!!
     
  8. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    I read the same things, it may have changed? Maybe there was a firmware upgrade, or maybe I'm just doing it wrong.

    Or it could only be gen2.

    Either way.. I'm still looking for a solution! I could always drive around but when you're parked in like waiting for your run your options are limited.
     
  9. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    Bump in case anyone has a good solution!

    Put in the TRD rear sway bar and saw a massive increase in cornering performance. Then I put in the Cusco front strut bar and saw another big jump in cornering performance. It drives around corners like it's on rails now, highly recommend both upgrades.
     
  10. Lightning Racer

    Lightning Racer Active Member

    Joined:
    Dec 16, 2015
    239
    320
    1
    Location:
    Anchorage, Alaska
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    What you described initially should have worked. Take a look at this:

     
  11. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    I just tried it again, let go of the throttle after I got the arrows pointing the right way and let off the gas.

    It charged to 4 bars and shut off. I tried again but it will only show the electric motor trying to pull the car forward. Did that for 3 minutes and didn't get another bar out of it. Can anyone try and see if it works for them?
     
  12. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    Hey guys, old thread but I wanted to post that I did figure it out. I was doing it right, but not letting it go long enough and not fully depressing the brake pedal.

    To charge the battery, put the car in drive, press the brake fully and hit the accelerator until it fully charges. It takes about two minutes from start to finish, and will only charge up to two bars from full.
     
    #12 TheChip, Feb 7, 2018
    Last edited: Feb 7, 2018
    Ernie stires likes this.
  13. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,114
    4,040
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    Will this method cause any damage to any component(s) later if done on a daily basis?
     
  14. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    The Prius cuts engine power to the wheels when the brake is fully depressed, so I can't imagine an issue. I've done it dozens of times with no problems.

    I'm not sure what would cause you to do this daily but the option is there.
     
  15. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,114
    4,040
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    Typically I have 3 to 4 bars after ICE goes off after cold soak start. I drive miles 1 & 2 are under 35mph, ICE kicks on after 1st stop sign. Miles 3 thru 4, ICE stays on at mile 3 and then all is warmed up at 4 miles and beyond. It won't fully charge up to 6 bars after 4 miles because lac of high RPMs so I'm thinking of brake + accelator every morning. Days I forget my work badge, I U-turn and drive back home and then drive back to work on same route. When ICE is all warmed up, all 4 first mile EV comes on as it should when driving back to work. No option for heater blocker just in case anyone is thinking :D
     
  16. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    If you're thinking of doing this for the MPG gain of having the engine warm, I can assure you it won't increase MPG. Driving the car will heat the engine up faster unless you happen to live in Antarctica in the winter. Instead of the engine doing work and pulling the car along, you'd just be burning gas at zero mpg for however long you let it go for. It frustrates me on cold mornings too, but until operating temps are reached that's just how it goes with the Prius.

    On the few single digit days I let the car warm up in the driveway before I went to work the MPG drops considerably. Sometimes after 5 minutes of idle it's still not at temps that allow full EV. Under even a small load the engine will put out more heat than flooring it at idle.

    Outside of needing to charge the battery for a small performance boost, I can't think of a reason you'd want to bother with it. Unless burning more gas just to get some fun out of an bit more EV is what you're looking for, in that case go for it!
     
  17. Hybrid Battery Exchange

    Joined:
    Nov 15, 2017
    66
    84
    0
    Location:
    Portland, OR
    Vehicle:
    2010 Prius
    Model:
    III
    In my experience a Gen 2 will charge up using the power brake method, car in drive, left foot on the brake, right foot fully on the gas. Initially it will charge @ 80amps, once the battery meter starts filling up it begins to reduce to a 40amp charge. A Gen 3 will charge @ 90 amps for about 5 to 10 seconds and will reduce to 3 or 4 amp charge after that. Getting on and off the gas lets you continue charging at high current.

    Gen 3 are particularly rough on their batteries, the entire center of the battery tends to degrade prematurely because it spends more of it's life at higher temps.
     
    DATALESS1, SFO, m.wynn and 1 other person like this.
  18. TheChip

    TheChip Senior Member

    Joined:
    Mar 17, 2017
    386
    1,207
    0
    Location:
    Misissippi
    Vehicle:
    2010 Prius
    Model:
    II
    Great information about that faster charging, I did notice the initial charge was faster and slowed down considerably. I will give it a try next weekend for the first event of the year.

    Would you agree with my statements about no negative effects from using this method? I've don't quite a bit of research that indicated power to the wheels is cut when the brake is fully depressed. I can't see any downside other than heat build up over time, although I don't see it being an issue for three autocross runs spaced over 30 or so minutes.
     
    DATALESS1 likes this.
  19. Hybrid Battery Exchange

    Joined:
    Nov 15, 2017
    66
    84
    0
    Location:
    Portland, OR
    Vehicle:
    2010 Prius
    Model:
    III
    The battery takes hours to cool down. As far as downsides you can evaluate that by watching your battery temps and block voltages using Torque app and a bluetooth dongle. If blocks in the middle of the battery start showing lower voltages I would suggest rearranging the battery, putting outside modules in the middle of the battery and the weaker modules outside along with reconditioning the battery, this would buy you time. I've seen a 3x gain in capacity in the usable operating range of 230 to 202 volts per pack after cycling the battery 3 or 4 times down to 168 volts, this would definitely prove useful in autocross, might not even need to charge between runs.
     
    TheChip, DATALESS1 and SFO like this.