The Prius learns some new “PHEV” tricks

Discussion in 'PHEV or Plug-in Hybrid Electric Vehicle' started by Right Lane Cruiser, Jun 12, 2009.

  1. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    [​IMG] Prius software upgrades bring 70+ mph_EV and the 100+mpg_PHEV is finally real!

    [FIMG=LEFT][/FIMG]Sean Welch and Wayne Gerdes - CleanMPG - June 11, 2009

    Few have been more excited by Prius PHEV conversion possibilities than members of CleanMPG. When we had the chance to drive Toyota’s OEM Prius-II PHEV-6/7 in Detroit two years ago, it was all right there. We drove it, experienced it, wanted it, and knew it was the future...

    Conversion companies (including A123System’s Hymotion) were going gangbusters supplying large format Li-Ion batteries with some SW control promising 100+ mpg. The promises were all but a guarantee yet when we finally had the chance to drive an example of the Hymotion conversion at a local MiHG meet, we were underwhelmed. The Prius retained its 34mph EV mode limit and the obnoxious warm-up reappeared anytime coolant temps fell below 159F. We could Warp Stealth at highway speeds without consuming a drop while drawing huge currents and shortened range but for an around town jaunt, the frustrating warm-up hits brought FE down to levels a std. Prius could beat.

    Since that time, a 52 mph hack has been developed by a CA. Hybrid repair company. It is triggered by disabling the Fuel Pump... allowing the Prius-II to maintain EV speeds up to 52 mph. This is nothing more than an exploitation of the built in "Out of Fuel" behavior.

    Our own Jay Groh purchased an A123Systems/Hymotion conversion and with a rheostat hack is able to force the Prius to believe the coolant temp is always “hot.” This tricks the computer system into foregoing the warm up routine and permits uninterrupted warp stealth and EV driving. He has demonstrated repeatable 200+ mpg commutes with this configuration.

    Now however, that magic 100+ mpg has arrived for everybody.

    Just a few days ago, the performance of Toyota’s own OEM PHEV was duplicated by a private company. Plug-In Conversions Corporation (PICC), founded in 2007, has done 30 conversions so far, but its business is picking up since it added a software upgrade to the package. PICC CEO Kim Adelman says, “We’ve augmented some of the systems; it’s mostly a software modification.” The result? 25mi AER and the very real possibility of not just 100mpg, but 170mpg tanks! This software modification was developed with the aid of Chicago-based Ewert Energy Systems, and it finally transforms the Prius into the type of PHEV anyone can achieve these numbers in with little effort. The kind that doesn't use the engine at all until its AER has been depleted.

    PICC takes out Toyota’s standard 1.3-kilowatt-hour nickel-metal-hydride battery pack, replacing it with a much-bigger 6.1 kilowatt-hour NiMH pack from its partner, Gold Peak Batteries Industries, North America. Gold Peak bought an undisclosed equity stake in Plug-In Conversions late last year.

    PICC’s conversion kit (adding 225 pounds) sells for $12,500, including one-day installation. The battery pack is warranted for three years. It “allows a Prius to perform much like the Chevy Volt, but for a much lower cost.” Those are fighting words for General Motors, of course. ;)

    The company says it has Argonne National Laboratory treadmill data that proves that, under certain specific drive cycles, it can achieve 170.27 mpg... but PICC says real-world achievement will depend on how you drive the car. “If you drive just 40 miles, you’ll double your mileage in our car. If you go, say, 100 miles, you’ll have 75 miles as a standard Prius and the results won’t be as dramatic.”

    Many of us here would be able to drive such a Prius to considerably higher than 170mpg tanks, with most of our driving done in pure electric mode and no gasoline used at all. How does that used Prius listing look now? ;)

    We can finally say that the future has arrived, and it looks mighty enticing from here!
  2. drimportracing

    drimportracing Pizza driver: 61,000+ deliveries

    Bring on the revolution! :D - Dale
  3. GrendelKhan

    GrendelKhan Well-Known Member

    Me want....
  4. cuchulain

    cuchulain He who posts articles

    Thanks Sean and Wayne, nice writeup.

    Certainly a nice new trick to have. Does the software hack incorporate a coolant hack?

    Have you seen a link to the treadmill data or have you seen the data?

    Is it similar to OEM PHV hack, i.e. leadfoot reporters can still knock the ICE on.

    Have you seen Wh/mile numbers? Blended or not?

    Good Luck
    There is video on there site:

    Did find something here:

    Enhanced Electric mode allows the vehicle to operate at speeds of up
    to 70mph in electric-only and allows for seamless transitions between
    electric-only and electric-dominant modes at any speed. Additionally, it provides
    a controlled warmup mode to prevent increased emissions.

    Enhanced Hybrid mode allows the vehicle to operate in a mode which
    heavily favors the electric system over the gasoline engine. While typical conversions
    will only provide up to about 7kW of power, this new system can
    provide full electric power (around 25kW) before using the gasoline
    engine. This creates the ideal parallel plug-in hybrid, providing full
    power for acceleration when needed, but optimizing for best fuel
    economy when in charge deplete (PHEV) mode.

    Where a converted Prius may have previously achieved only 60-80mpg at highway speeds, a
    converted Prius with this latest technology may achieve in excess of
    150 mpg. An early prototype of the system was tested at Argonne
    National Labs earlier this year and achieved 170mpg on the realistic
    standardized highway test (a combination of 55mph and 65mph highway
    driving.) For many trips, 200mpg is now possible without the use of EV
    mode.During Argonne tests, this system was found to comply
    with SULEV/PZEV emissions ratings.
    Last edited by a moderator: Jun 12, 2009
  5. lightfoot

    lightfoot Reformed speeder

    The mileage claims for plug-ins need to include electrical usage. Otherwise it's meaningless to claim that a plug-in gets "170mpg" when a substantial part of the drive energy comes from a second source (the electrical grid). And when the "mpg" decreases once one gets beyond the AER range. Logically, this practice is equivalent to trailering a car to the top of a mountain, coasting it down, and claiming "under certain drive cycles it gets infinite mpg!!". In this case. the second energy source is the potential energy from elevation, in lieu of the energy supplied by plugging in the larger battery.

    Plug-ins are absolutely wonderful, but unless the electrical energy usage is factored in (preferably the energy used to charge the battery, not the energy supplied from the battery), the mileage claims for plug-ins will lose all meaning in a welter of claims and counter-claims for different scenarios. And potential buyers will just be confused.

    Personally, I'd like to see ALL hybrids, even the ones without extended-range batteries, be "plug-in". And have built-in block heaters tied into the charging system, especially for hybrids with smaller batteries that will be using their ICE's more right after startup.

    Ultimately it may happen that BEV's will be optimized for shorter-range uses, possibly with battery-swap options for longer range needs. Not having ICE's may help make them cheaper and lighter (which will probably translate into longer range). And present PHEV's may morph into vehicles optimized for longer range usage, as least until gas prices rise so high that they become impractical.
    Last edited: Jun 12, 2009
  6. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    That's an awesome video find, Andrew! Thank you!

    Good point, John -- though most of us would be just psyched to be able to eliminate gas completely from commuting trips. :D
  7. cuchulain

    cuchulain He who posts articles


    About maximum power, using the software hack the max speed requirement (approx 58mph) of the UDDS cycle is covered but the cycle requires a max of 35-40kW of wheel power for one section but most of the power stays at or below 25kW. So except for one section emissions should be vastly improved. Previous PHEVs were also underpowered.

    Max power of UDDS, page 9

    Good Luck
  8. diamondlarry

    diamondlarry Super MPG Man/god :D

    Ok, I think I may need a new keyboard; it seems I've been drooling excessively while watching that video.:p With my commute and traffic patterns for other driving (errands, etc.), I would almost never need to use gas again.:flag:
  9. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Andrew:

    ___Thanks for digging up the vid...

    ___After seeing it, I suspect they have hacked the Prius' programming but they may not have been entirely successful at breaking all of the OEM code. I saw no tach but they may be in Warp Stealth above 41 mph thus there are no limits to speed other than current draw (this is a good thing) but the OEM PHEV in Detroit drove to 62 without any RPM. I sure would like to drive it with a ScanGauge-II to verify what they have defeated and what they have not.

    ___The other item was the crawl up to 70 to minimize current draw below about 125 amps apparently so as to stop the ICE from coming on to help power the conversion I am quite sure.

    ___The guys mentioned some speed thresholds but I wonder if they have an understanding of the MG1 interaction and limits or if they just found a way to keep the injectors shut down with the ICE spinning up from 41 mph on up like a normal WS?

    ___Overall, a very good job :)

    ___I will try and contact them today for a test ride myself.

    ___John, in this case, many of us here would attempt to place the Prius into an all-EV mode and than we can all but guarantee we are working on < 250 Wh/mile. If there is a mix, so be it but it will likely be far less onerous than one might expect. ICE on during WS costs fuel but not nearly as much as without.

    ___My next question is how did these guys get the ANL to take there vehicle in for testing? One of the brothers probably works there and thus the equipment to pull the binary code (thanks Sean ;)) and reverse engineer what was needed possibly?

    ___Lastly, this is the coding hack that Toyota "did not want to be let out" due to allowing the PHEV promise to be realized. Now that it is, it will probably be open source in no time with the resultant back pedaling, disclaimers and we disavow all knowledge like statements :D

    ___Good Luck

  10. jimepting

    jimepting Well-Known Member

    Your post started me thinking. Actually, all the "equivalent" MPG number from differing fuel sources suffer from this oversight. Ethanol as a fuel has long been criticized on this count. It takes considerable fuel, mostly diesel, to produce a gallon of ethanol. Then, the gallon of ethanol has less energy, which also has to be accounted for.

    I suppose that if we took the argument to the extreem, and we probably should if we are interested in environmental impact, we would find a better way to account for all the fossil fuel used in the production of the calories that actually gets consumed driving a car. If so, all of our FE numbers would be much lower, but much more realistic in environmental terms.
  11. diamondlarry

    diamondlarry Super MPG Man/god :D

    I just sent an email asking them for pricing information. I'll post any replies as I get them.
  12. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Larry:

    ___When I first read about this, I believe it was a $1,500 SW upgrade (if you can purchase it separately) from Ewert. For the entire conversion including the new SW, it is $12,500 from PICC. Jay will be particularly interested in the SW patch as that would make his A123Systems conversion sing without the BS he is having to deal with now.

    ___We can also expect to see a little funding go back into Hymotion to break the code as well because their conversion is essentially obsolete... As are the rest :rolleyes:

    ___A/C draw at those higher speeds will make for yet another interesting metric to take into account for the ability to remain in an ICE-Off condition as well?

    ___Finally we will now see just how long the OEM Inverter and MG2 will last when rode hard and put away wet day after day after day :D

    ___Good Luck

  13. mparrish

    mparrish Rosie the Riveter Redux

    Surely they are in WS at 70mph? I'd be reluctant to take her up past 62mph & 10k RPMs for the MG without either spinning the ICE or someone convincing the "community" why it is unnecessary.

    It's super warp stealth (SWS)! :)
  14. mparrish

    mparrish Rosie the Riveter Redux

    By the time he's all done, Jay's Prius will need to be donated to some auto museum much like Einstein's brain. ;)
  15. diamondlarry

    diamondlarry Super MPG Man/god :D

    I wonder if they take payments?:D I was also wondering about the inverter/MG2 longevity issues.
  16. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Larry, I wouldn't worry much about longevity at the speeds you drive. ;)
  17. TheForce

    TheForce He who posts articles

    The software would be nice but because of the way the Hymotion battery works I would not want to use the software to make a continuous 100+ amp draw off the battery. Especially all the way up to 70mph. The reason is that if you draw more than about 30A the stock battery will start to lose SOC. When the SOC gets lower the fake SOC gets lower. This can go all the way down to %40 and I believe even down to %30 since the Hymotion is still faking the SOC. I have not got it down that far to find out and I don't plan to test it either. The software upgrade would be nice so I would not have to worry about it kicking out of EV through the 35mph and 41mph speeds but I'm not going to pay that much for it. I would pay maybe $100 for it and maybe $500 at the most.
  18. diamondlarry

    diamondlarry Super MPG Man/god :D

    You're probably right. I doubt I would ever get much above 55 mph if even that fast.:p
  19. lightfoot

    lightfoot Reformed speeder

    I'd settle for simply the amount of energy going into the vehicle, and figure the costs of generation and delivery separately. The problem with electricity is that there are so many modes of generation, each with different costs.

    But as Wayne pointed out, plug-ins would operate in EV mode as much as possible, so mpg numbers for their gasoline usage are essentially meaningless. Short EV-only trips would give essentially infinite "mpg"; longer trips that would drain the plugin charge would give a lower figure. Basically a sliding scale. I think the "150mpg" number for the Volt came from 40 miles of EV followed by some number of miles with the onboard generator running.

    Plugins will reduce gas usage tremendously, which is great.
  20. Taliesin

    Taliesin Well-Known Member

    These two sections almost contradict each other.

    One of my main reasons for cutting fuel usage is to keep us from sending money overseas, so the mpg numbers for gas usage still mean a lot to me.

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