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

Review UPDATE Hymotion plug-in battery after 100,000 miles, 14 years, and 4000+ cycles

Discussion in 'Gen 2 Prius Accessories & Modifications' started by TheForce, Jun 17, 2022.

  1. TheForce

    TheForce Stop War! Lets Rave! Make Love!

    Joined:
    May 30, 2005
    3,461
    537
    0
    Location:
    Wheelersburg, Ohio
    Vehicle:
    2006 Prius
    Model:
    N/A
    Its been a long time since I've been on the forums but I thought I should give a quick update on the status of my 2006 Prius that I had converted to a plug-in back in 2008 with the Hymotion system. I miss you guys sometimes but I've been pretty busy with other distractions. :) Plus I dont think I can contribute much with my only knowledge of a gen2 Prius.

    Original review
    REVIEW: Hymotion Battery Plug-In Prius | PriusChat

    I dont have any nice graphs or data to go along with this but I will tell you what my experience has been driving this car for so long.

    I have not had any real major issues with my Prius. Just the usual maintenance and replacement of the coolant pump. Except 2 weeks ago the high voltage NiMh pack finally failed. More on that later.

    I currently have about 120,000 miles on my car and an estimated 100,000 of those as a plug-in with the Hymotion system.

    The original Hymotion pack I had installed was replaced after a year or two for a recall or something. I dont remember why exactly but I dont think I was having any trouble with it. I was in Wisconsin for Hybridfest and they wanted to replace it. It was replaced with another pack that had about the same cycle life on it.

    I estimate that the cycles I currently have on it is around 4000 cycles or more. Using it at least 5 days a week over this many years.

    Like new it would use about 5.2kWh from the wall and now its only putting about 2.5kWh into the pack. According to my can-view I went from about 17.5Ah down to 7.5Ah of usable capacity. For 4000+ cycles this seems to be about how much capacity I would lose after 4000+ cycles so I'm not really that surprised.

    My strategy now is to only turn the pack on during the highway part of my 22 mile round trip to work and only use a little bit in the city. In the summer as long as I dont run the A/C I can still get about 100mpg. I have not tested my current EV only range but I know its about 7.5Ah usable capacity now.

    So was it worth $10k back then? I had the money back then to do this and its something I wanted since EVs were not available so to me it was worth it. Has it paid for its self? I did not keep track of it exactly but if you compare it to a 25mpg car over 100,000 miles then I think I'm close to break even. At lest that's how I always calculated it.

    So what am I going to do with this car now? Well I'm really hoping to buy either a Tesla Model Y and or an Aptera in 2023. I need to make room in the garage for another car so I will most likely try to sell my Prius. If I was not planning on selling it I would try to install about 10kWh prismatic pack in the trunk for the Hymotion system. I think that would be a good project to keep this car going. If anyone has done something like that let me know. I would like to see your work!

    So what about replacing my NiMh battery? Well 2 packs were under voltage or loss of capacity a few weeks ago from this posting. Since I'm still at least a year away from buying an EV I decided to replace the battery. I found that there is a LiFePo4 replacement for it so I went with that. What I purchased was the https://projectlithium.com battery. Its about 2x the price of a replacement NiMh pack but I thought it would be worth the price if not for the resale value then I could reuse the cells for a different project. Since I could not remove the Hymotion pack to install these new cells it made it harder to get the NiMh pack out. If it was not for that replacing the NiMh with these would have been so much easier. If anyone near me wanted to upgrade their car with these lithium cells I would gladly help since its so easy to do. I dont want to give a long review of them but as of now I give these an A+. There are plenty of videos and information on these if you need more info.

    I think thats all I can think of at the moment. If you have any question about my Hymotion plug-in battery feel free to ask and I will try to reply within 24 hours.
     
    Meg&Bear, ColoradoCrow, ToyXW and 6 others like this.
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    thanks for the update, congrats on a great run! miss you man :cool:
     
    TheForce likes this.
  3. Yosarian

    Yosarian Junior Member

    Joined:
    Oct 9, 2017
    35
    22
    0
    Location:
    Delaware
    Vehicle:
    2005 Prius
    Model:
    Two
    Interesting, and serendipitous. I have a 2005 that's something of an odd duck. Buddy who sold it to me bought it from the original owner w/ dual NiMh battery set up and a side port for some sort of external charging. He removed that gear & converted to a single battery set up that's still getting 48.4 at 136k miles, but both original batteries were traded in for the single rebuilt one.

    Have another '05 that I'm putting on the road for a family member, and was interested in purchasing a new module set from Dr. Prius/Project lithium team, but I can't find any contact number to call, and they've been completely awol in replying to emails to their sales info address. Couldn't get their store front to give me a correct shipping cost (it kept adding more and more freight charges that didn't make any sense) but since I can't get anyone there to respond through their proffered email system, and there's no number to call, I'm stuck. Glad to hear you've had a good experience w/ them, as I now have two more that I'd like to convert, but I'm not feelin' much love thus far. Any tips would be appreciated.
     
    Meg&Bear and PriusCamper like this.
  4. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,130
    505
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    #4 alftoy, Jul 16, 2022
    Last edited: Jul 17, 2022
    Meg&Bear and Yosarian like this.
  5. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,774
    4,372
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Thanks @alftoy for the heads up... I'm in touch with them at least once a week but usually more often and can do all I can to help get you hooked up. There's very few packs remaining so it's urgent you get back online and get your order in. Shipping a ~40 pound box of lithium batteries is not cheap and costs a bit over $100.

    Sounds like your problem is you have erroneous charges in your shopping cart?

    Here's a few things to try one or all of:

    1) empty out shopping cart and start over
    2) clear your browser history
    3) go into incognito mode and enter your info with a different email address

    And as always, if you use my affiliate link that's in my signature to order I'll put as much time as you need into this to get your issues resolved.
     
    Meg&Bear and Yosarian like this.
  6. Yosarian

    Yosarian Junior Member

    Joined:
    Oct 9, 2017
    35
    22
    0
    Location:
    Delaware
    Vehicle:
    2005 Prius
    Model:
    Two
    Did and done, thanks, but still not loving the complete lack of response and total lack of contact means. Glad you're in touch with them weekly. I would have appreciated speaking to someone at least once, especially since my partner and I were seriously considering adding their batteries to our shop & mobile services. Still interested, we're just a little more old school and actually use our phones as phones too.
     
    Meg&Bear and PriusCamper like this.
  7. Yosarian

    Yosarian Junior Member

    Joined:
    Oct 9, 2017
    35
    22
    0
    Location:
    Delaware
    Vehicle:
    2005 Prius
    Model:
    Two
    And the functional problem that I was having w/ their site was that it added an extra shipping charge. I full well realize that 40 lb. boxes of placarded batteries don't ship for free, it's just kinda silly that I need go through Priuschat to get squared away, but thanks. Seems we're now on track.
     
    Meg&Bear and PriusCamper like this.
  8. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,774
    4,372
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Good to hear! I'll personally communicate with him for you if anything comes up... He always replies to me the same day I message him. I'll also let him know you're a shop that's interested in long term business. He's been very generous to me and certain he'll be that way with you too.

    I think in your case that situation was that you hadn't made the purchase yet so your were a prospective customer rather than an existing customer and he gets lots of people who never buy who ask him lots of questions and he has a limited number of experienced employees.

    I remember one dude a couple months back. We both had several long emails with him regarding super cold weather performance and not only did he not purchase but he got into a Facebook Prius group and said all kinds of dishonest negative stuff and claimed we didn't help him out and I'm like, "I spent more than an hour replying in detailed emails with solid references." But it was the usual social media troll that asks you to back up your claims with references and then you do and they discount them as invalid faster than the amount of time it takes to skim through them. Those kinds of people aren't worth the time you put into it.
     
    #8 PriusCamper, Jul 17, 2022
    Last edited: Jul 17, 2022
    Meg&Bear likes this.
  9. T1 Terry

    T1 Terry Active Member

    Joined:
    Jan 4, 2015
    585
    297
    0
    Vehicle:
    2006 Prius
    Model:
    Plug-in Advanced
    I have a 2006 Prius with the Enginir kit, a 74 cell 40ah battery so nom. 240vdc. The range on ICE Kill EV only mode was roughly 80km at 80km/h max speed, fine around town but useless on the highway. If I kept the travel distance to less than the extended range pack capacity, 1 averaged around 2.5ltrs per 100km , a Google calculator says that is 94 US MPG. Not quite are good as your 100 MPG, but not bad.
    I'm in the process of fitting 84 x 55Ah LTO cells into Prius. Rather than loosing the boot under floor area where the spare wheel and jack could go and wasting the spare wheel well, I looked at mounting the cells with 12 in the wheel well, a layer across the rear floor and the rest built 3 layers deep to match the shape of the original NiMh battery.
    It would have fitted nicely but I had another think about it changed to 48 cells where the original NiMh battery was and the remaining 36 cells in where the spare wheel went. This involved squaring up the spare wheel well that eventually frustrated me so much I've cut it out with an angle grinder and I'm building a sheet steel box to replace it. This way, the original plastic insert will fit under the floor so I can carry the spare wheel, jack and plug in cord for the fast chargers.
    The 55Ah LTO cells can be charged at 10CA if you really want to, that's around 6 mins from fully discharged to fully charged, but I doubt I'll ever be in that much of a hurry, 2CA would be 110 amps and recharged in 30 mins, I'll be happy with that.
    The other advantage is no more NiMh battery and the battery being full after a bit of down hill regen, the best regen I've seen on my scan gauge is 150 amps so a flat battery could handle 20 mins of constant regen .... that's a very long hill :lol:

    T1 Terry
     
    Meg&Bear likes this.
  10. Bryanpluginprius

    Bryanpluginprius New Member

    Joined:
    Oct 20, 2022
    1
    2
    0
    Location:
    Colorado
    Vehicle:
    2005 Prius
    Model:
    Two
    I also have a Hymotion conversion that is still going strong. I have had mine since 2009 and 35k Mike's. It sitting at 174k. It's been a daily driver 5 days a week. I don't have any technical data. It used to do 30 or so miles before shutting down on flat ground at sea level where it spent most of that time for the last few years it has been in Denver and these days on my commute it shuts off after about 11-12 miles. I never had a problem with the system still works every time. Very happy with the investment back then. Glad to hear other units still kicking it .
     
    Meg&Bear and TheForce like this.