Replace battery pack in Out of gas mode

Discussion in 'Prius PHEV Plug-In Modifications' started by menardsy, Oct 25, 2013.

  1. menardsy

    menardsy Junior Member

    Joined:
    Dec 11, 2011
    63
    11
    0
    Location:
    canada
    Vehicle:
    2004 Prius
    Model:
    Two
    Not at all! The pack is regularly balancing itself (the bms start a balancing mode every 15 charges).
     
  2. astrand

    astrand PHEV Guru

    Joined:
    Aug 19, 2007
    33
    12
    0
    Location:
    Linköping, Sweden
    Vehicle:
    2004 Prius
    Model:
    N/A

    I disagree. Here's why:


    This is only a problem if you are driving in a "Forced EV" mode. There are plenty of other options as well. You can use a blended/assisted mode or a device such as the Ewert Energy Systems "Hybrid Energy Manager". Besides, I've been driving in "Forced EV" mode for years, and my experience is that driving in cities etc works perfectly fine. Never had an incident or anything. If lack of power would make a vehicle unsafe, then you would have to ban all kinds of vehicles.


    With Prius gen 3, there's no need for spoofing, you'll just have to keep the voltage at a decent level. For gen 2, spoofing is an advantage. However, any kind of battery system requires a BMS, so assuming you are using a flexible BMS, you don't need any extra device. To spoof the gen 2 SOC etc, the only extra thing you need is a BMS with 2 CAN buses and some software. It's not that difficult.


    Again, you don't have to use OutOfGas (Forced EV) mode, but if you want, the fix is cheap.


    Again, I've been driving in this mode for years, and I must say that this is not much of an issue. One way to look at it is this: As an alternative, you could have one fully electric vehicle (thus with a limited range), plus one normal gasoline vehicle. In the morning, when you are leaving home, you have to select the vehicle depending on how far you should go. However, with a PHEV Prius, you are instead selecting the drive mode. With the pure EV, as well as the Prius PHEV in Forced EV mode, you have to stop when the batteries are depleted. But unlike the pure EV, the Prius allows you to just restart and continue driving. The pure EV would have to be towed away. Plus, you only need one car instead of two.


    Nobody is sugggesting that one should install a larger motor, inverter etc. When it comes to selling a PHEV Prius, my experience is that people are actually quite interested in buying such Priuses.


    In general, it's true that the Prius PHEV conversion business is full of failures. Most companies are out of business. However, saying that this is because the Prius is not a good candidate for PHEV conversions is wrong. In my opinion, the reason why most Prius PHEV conversion companies are gone is because the EV business, in general, is quite tough. Batteries are expensive, and many battery vendors is also out of business. Gasoline prices are low. Plus, creating an advanced quality product such as a PHEV conversion kit takes a lot of time, money and effort. Creating a product that works is one thing, creating a product which can be sold with a profit is something totally different: It's likely possible, but requires a larger investment and more patience. There's a huge difference between the kind of cost and system optimizations that large company such as Toyota, Nissan or Tesla can do, compared to a small garage company, and even the big companies are sometimes struggling with profits.

    I think that Prius PHEV conversions still makes sense, and we will probably see a few more interesting conversion kits in the future.

    Br,
    Peter
     
    dave77 and planetaire like this.
  3. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    978
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four

    I agree to disagree but, my reasoning is very sound and logical here's why:


    The fact that you never had an incident doesn't negate any safety concern. I know of no vehicle that weighs 3000 lbs and has a 44 hp motor. Yes, it has good torque off the start but not good acceleration beyond that. Sometimes you need acceleration to get you out of a sticky situation. I personally consider that unsafe. As for using the blended/assisted mode, yes, you can use it (much safer) but, give it a little too much gas and the ICE turns on. In this mode you'll likely net about 65 mpg city for most people. That would take decades for a return on your investment.


    Apparently its easy for you but, keeping the voltage at a "decent" level, limits the charging of your stock HV battery thereby limiting the benefit of the PHEV conversion. Either way, the BMS with 2 CAN busses and some software would cost hundreds of dollars (as I rightly stated).


    Again, not using OOG Mode limits the benefit of the PHEV conversion. I agree you don't have to use it but most people I know won't want to pay $10,000 for a 12 or 13 mpg increase. Driving in blended mode and achieving 65 mpg would be a challenge for a lot of people especially if they have a short commute (which is why you want a car with all electric mode as an option). Those people would want OOG mode.

    I'm suggesting that most will want a larger electric motor to mitigate the poor acceleration and safety issues. I couldn't imagine spending all that dough on a PHEV conversion and having all these issues to deal with. The logical next step is to not want to give up and fix the problem. The only fix is a larger motor and a new inverter. That's the way I see it anyway.

    As I stated, we will have to agree to disagree. My whole point of the original post is so anyone considering a Prius PHEV conversion will have a myriad of opinions from which to base their decision. I am an avid supporter of any idea that limits fossil fuel consumption but, the implementation of the idea has to make sense from a safety and a financial standpoint. I understand that if you're careful, you can get away with less power but, I also think one should take on this endeavor with eyes wide open.

    Br
    Phil
     
  4. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,357
    3,161
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    This is one the only updates I've heard about the MD-Tech kits.

    There still appears to be issues.
    - Sounds like a few months from first ordering to receiving the kit.
    - Sending money for an item (extra converter) and not receiving it nearly a year later? Whaaa??
    - kit overheats in warmer temps.

    Still to risky for me to recommend to customers.
     
    dave77 and usnavystgc like this.
  5. menardsy

    menardsy Junior Member

    Joined:
    Dec 11, 2011
    63
    11
    0
    Location:
    canada
    Vehicle:
    2004 Prius
    Model:
    Two
    I must admit that I will think about it twice today. This kind of converter is only sold by them. So if it breaks I'm doomed.

    I really like the idea running on electric mode only. I was thinking about selling this kit and using at 240 v battery and limiting the current with some kind of high voltage controller.
     
  6. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,357
    3,161
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    I know of people who have stacks of non-working aftermarket PHEV parts from out-of country suppliers.

    I hope you don't become one of those people.
     
  7. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    978
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four
    Menardsy, I love the idea of running on electric mode only but, the Prius is just not the car for this. If you want an E Car (for the city, which is all they're really good for at this point), I recommend the Mitsubishi for a single commuter on a budget. If you want an E Car with extended range, get yourself a Leaf with a range extender that you can tow behind it.

    As for converting the Prius, it is not practical to run on electric only and there are so many limitations to OOG mode beyond the lack of power. The Prius is just not meant for electric only operation. We can want it to be all day but, that doesn't change anything. No kit is going to fix that, no amount of batteries will change that. Only a redesign of the car will change that.
     
  8. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    978
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four
    I'm one of them.
     
  9. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,357
    3,161
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    I bet my stack is bigger than your stack, usnavystgc. :)
     
    dave77 and usnavystgc like this.
  10. menardsy

    menardsy Junior Member

    Joined:
    Dec 11, 2011
    63
    11
    0
    Location:
    canada
    Vehicle:
    2004 Prius
    Model:
    Two
    I agree about the third gen that doesn't need oog mode, but it also doesn't have it. The downside is that you can't dump high current in its battery as you can do with the gen 2 in oog mode.

    Whatever we do there is compromise...
     
    usnavystgc likes this.
  11. menardsy

    menardsy Junior Member

    Joined:
    Dec 11, 2011
    63
    11
    0
    Location:
    canada
    Vehicle:
    2004 Prius
    Model:
    Two
    The Mitsubishi is around $35,000 here in Canada, I find it hardly a budget car.
    My 2004 prius probably don't worth much right now. I already invested in the kit so financially speaking it's probably better to keep it.
    The Mitsubishi is doing 0-60 in 13.5 seconds which is quite slow by today standards. It can also be risky in some situations...
     
  12. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    978
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four
    Wow, what a difference, its only $23,000 here. Sorry I mentioned it, I had no idea there would be a $12,ooo price difference.

    I have no more suggestions or solutions for you. I wish you the best of luck.
     
  13. astrand

    astrand PHEV Guru

    Joined:
    Aug 19, 2007
    33
    12
    0
    Location:
    Linköping, Sweden
    Vehicle:
    2004 Prius
    Model:
    N/A
    If you look at lbs per hp, a PHEV Prius in Forced EV mode has about 2900 lb / 25 kW = 116 lb/kW. A
    Light quadricycles (Motorised quadricycle - Wikipedia, the free encyclopedia) is often 770 lb / 4 kW = 192 lb/kW. That's worse.


    As I mentioned, the Ewert HEM solves this, but admittedly at an extra cost. But even without this device, I think that the blended mode works great. On a Swedish highway, the speed limit is usually 110 km/h = 68 mph. With a stock Prius, you get perhaps 45 MPG. With my PHEV Prius, I instead get 80-90 MPG, for something like 75 miles. I think this is great, and it saves money. The question return of investment is difficult though, and depends on many factors.


    Sure. EV stuff are expensive. Personally, I don't mind paying a few hundred dollars for an advanced BMS system. I lot of people which buys a factory EV/PHEV immediately orders charging cables etc for a lot more than that. Want a high power EVSE? That's something like $649.00! (ref: Toyota : EVSE Upgrade, Low-Cost EV Charging Solutions).

    Br,
    Peter
     
    dave77 and planetaire like this.
  14. astrand

    astrand PHEV Guru

    Joined:
    Aug 19, 2007
    33
    12
    0
    Location:
    Linköping, Sweden
    Vehicle:
    2004 Prius
    Model:
    N/A
    This is wrong. The Gen3 also have an OutOfGas (Forced EV) mode, and it works basically as with Gen 2. Blended mode also works fine. You cannot use / does not need SOC spoofing with BMS2 or similar device. OTOH, the contactor logic needs to be slightly smarter, but it's fairly easy.

    Br,
    Peter
     
    planetaire likes this.
  15. menardsy

    menardsy Junior Member

    Joined:
    Dec 11, 2011
    63
    11
    0
    Location:
    canada
    Vehicle:
    2004 Prius
    Model:
    Two
  16. astrand

    astrand PHEV Guru

    Joined:
    Aug 19, 2007
    33
    12
    0
    Location:
    Linköping, Sweden
    Vehicle:
    2004 Prius
    Model:
    N/A
    Thanks. I was actually beeing a little fussy. Let me clarify: Both the gen 2 and gen 3 has a fail safe mode where the ICE is disabled and which allows you to drive only on battery power. I call this "Drive on motor mode"; this is what Toyota uses in some documentation. There are multiple faults which can trigger this mode. On gen 2, running out of gas is one (although a clumsy one) method of triggering this. Cutting power to the ECM is better. The gen 3 also as a "Drive on motor mode", but apparently running out of gas does not trigger it, but cutting power to the ECM still works fine.
     
  17. menardsy

    menardsy Junior Member

    Joined:
    Dec 11, 2011
    63
    11
    0
    Location:
    canada
    Vehicle:
    2004 Prius
    Model:
    Two
    Thanks for clarifying!

    I just read some post on Techstream that allow ECU reprogramming. I wonder if it could reprogram the maximum current we can send from the phev kit to th hv battery before it disable the hybrid system...
     
  18. menardsy

    menardsy Junior Member

    Joined:
    Dec 11, 2011
    63
    11
    0
    Location:
    canada
    Vehicle:
    2004 Prius
    Model:
    Two
    Ok,
    Some news about my MD-TECH kit. The battery pack, like other stories from Enginer kit users, has started dying.
    Half of the battery pack (1 24v pack) can no longer hold its 2kwh charge. I estimate about 1kwh remaining available. I am a bit disappointed because I was expecting the new BMS to improve the battery health. I have about 300 charge-discharge cycle since I started using it about 9 months ago.

    One good thing is that the converter seems to hold on...

    Sylvain
     
  19. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,357
    3,161
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    Why not manually balance/charge pack rather than rely on BMS. If you can get things stabilized you can keep things in balance quite a while if you monitor it regularly and manually adjust as necessary.
     
  20. lopezjm2001

    lopezjm2001 Senior Member

    Joined:
    Apr 14, 2009
    1,146
    403
    5
    Location:
    Sydney Australia
    Vehicle:
    Other Electric Vehicle
    Model:
    N/A
    Hi Sylvain,

    Have you checked the logging data for each of the 16 cells on the BMS's SD memory card. Using Microsoft Excel computer program you can graph the 16 cells logged values during the charge and discharge cycles. The graph will show you why you lost battery capacity if it has logging data from day one until now. You can lose capacity due to extreme cold weather during charging in winter and get most of it back later in summer. You can upload the BMS's data file if you like.

    Jim
     
Loading...