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

Build Hybrid Battery Maintenance Gear For Under $100

Discussion in 'Gen 2 Prius Main Forum' started by PriusCamper, Mar 25, 2021.

  1. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,132
    506
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    Exactly what was quoted.

    " The 100K resistor is used to speed up the discharge of the high voltage of the Mean Well supply when you switch to "Discharge" or power OFF. Without the resistor (commonly called a "bleeder resistor") the supply will take much longer to reduce the high voltage to safe levels if you need to tinker inside the case. I connected D1 and R1 right near the charging harness socket on the front panel."
     
    Dxta likes this.
  2. Solman636

    Solman636 Member

    Joined:
    Aug 28, 2014
    91
    31
    1
    Location:
    Florida Panhandle
    Vehicle:
    2008 Prius
    Model:
    Two
    Thank you, Alftoy! That was just what I needed to know and pretty much what I guessed. Thanks for taking time and your patience with my questions. You're a good scout! And maybe I will follow your advice...and since the dogs won't allow me to ride the ebike that way anymore I suppose I maybe I'll just walk! Ooops...that idea won't work. Just looking out the window I see my neighbor who walks that way every day who told me a couple months ago that same dog bit him on the leg! Haha...still need the protective hull of the Prius on this road it seems. Thanks again for your help, sir!
     
  3. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,132
    506
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    Maybe @jerrymildred can elaborate on what happened when he fully grid charged his HV battery and then started the Prius. Or maybe someone can explain if that is pertinent to fully charging a Nexcell LFP pack to 100% in a Prius without the BMS being aware that the pack is at 100%.

    2010 Prius II HV Battery Reconditioning | Page 4 | PriusChat
     
    #103 alftoy, Aug 6, 2022
    Last edited: Aug 6, 2022
  4. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,852
    4,399
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    So I had a list of things to go over in an email to nexcell today and included your idea for charging the battery to ensure 2 miles of EV range and they raised an additional concern that I'd not thought of. And not much for hills in Florida, but it's still a valid point because any regenerative braking is going to charge an already fully charged pack:

    "...if customer lives on the hill side and he charge up the battery to 100% then roll the car down the hill, the regenerative braking is going to overcharge the battery and damage it before the BMS re-calculate and stop charging the pack. There is a time delay before BMS realize that the battery is already fully charged and that’s why I never agree on this type of abuse."
     
  5. Solman636

    Solman636 Member

    Joined:
    Aug 28, 2014
    91
    31
    1
    Location:
    Florida Panhandle
    Vehicle:
    2008 Prius
    Model:
    Two
    For the official record I will abandon the idea of charging the new Nexcell LFP battery based on the consensus on this forum. It was just an idea. The possibility is interesting but too difficult and risky for the minor advantages. My goal of 2 miles a day with the LFP has already been done easily a couple of times for fun since I got the new battery and easily keeps within 50-60% SOC. That's all I need for 95% of my daily driving, but clearly the right charging method and hardware within limits is necessary or shorter battery life or worse will ensue. There certainly is no support for the idea among those I have asked and no motivation to find out since the risk/benefit ratio unsuitable. But if any try it I will be interested to hear about it. Yet, I am not encouraging the idea either.

    I saw Jack do a video with a 5 mile EV run with his LFP last year. That is stretching way beyond what I wanted to do daily. Naturally, Jack can NOT endorse the idea of charging the Nexpower battery in any way except with the Prius itself in normal operation mode. Nexcell can not assume the risk for untried and unregulated procedures by DIY electricians to grid charge a battery that even with all its fantastic properties and results is still considered by some as experimental. The LFP battery for that demo was no doubt force charged with ICE and Prius inverter at much higher amps and in only a couple of minutes and that undoubtedly would also not be recommended routinely either on a regular basis. As a matter of fact, I think Jack has a DON'T video that states that fact to those with newly installed batteries. I concede that the 2 mile goal of grid charging the LFP experiment described here is not controlled enough for most DIY people including myself, and there are real dangers with charging. But that is why I came here looking for answers, and I got the message. By the same token, a lot of people these days are charging Nimh at low current with various chargers, and as we have heard one man even lost an eye recently in the process of reconditioning an HV battery with a brand name charger, and there have been other catastrophes as well it appears. It is good that this forum exists to share what works, what is safe and what is dangerous. Thanks for the input to all of you.

    BTW, today after changing my rotors and brake pads I took the car out to bed in the pads. This was the first trip out since I did the Nexpower upgrade. I was shocked at the mpg on my 11 mile run. Haven't ever seen the mpg that high ever. Who knows how accurate but regardless I was impressed as I have never seen this. Many years ago I did get much better mpg when the battery was younger but never a reading quite like this. Bottom line is I am very pleased with the results of the Nexpower battery!

    upload_2022-8-6_21-49-10.png
     
    #105 Solman636, Aug 6, 2022
    Last edited: Aug 7, 2022
    PriusCamper likes this.
  6. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,132
    506
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    Yosarian likes this.
  7. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,852
    4,399
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Yeah, but number of cycles a battery is good for is not a very useful measure. But maybe there's some tricky math in how you measure cycles in a battery pack that's designed to never be fully charged or fully depleted? Based on Taxi cabs going 400K miles with no issues with battery pack, I'm thinking one cycle between 40% & 80% charge counts as a very, very small percentage of one full cycle. Likewise the amount of times you recondition a module is miniscule compared to its rating for how many charge and discharge cycles it's good for.
     
  8. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,132
    506
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    Linked post was referring to the statement quoted below, in reference to @Solman636 wanting to continually charge the Nexcell LFP to 100%

    "has anyone tried rigging up a system that allows for grid charging of the stock battery so you always start at 100% charge state."
     
  9. Vickstew

    Vickstew Junior Member

    Joined:
    Sep 14, 2022
    16
    9
    0
    Location:
    kirkliston
    Vehicle:
    2010 Prius
    Model:
    N/A
    I know this is an older post but I am trying to build this for my Prius gen 3 and wondered if there are any changes needed for UK grid power. Mine just blows the 2Amp fuse every single time :( Thanks
     
  10. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,132
    506
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    Best to follow along with Euro member tips such as Abernabe, disregard suggested diodes.
    DIY Grid Reconditioning Charger | PriusChat

    Hard to comment without knowing exactly what you have built.
     
    Vickstew likes this.
  11. Vickstew

    Vickstew Junior Member

    Joined:
    Sep 14, 2022
    16
    9
    0
    Location:
    kirkliston
    Vehicle:
    2010 Prius
    Model:
    N/A
    Thanks for getting back to me on this alftoy. I had looked through what you suggested already.
    I was following the guide on insight central for the OlRowdy01 V2 grid charger build (I'm a new member so can't post links yet) but using the meanwell substitutes for prius 2/3, Finally got it working tonight though without blowing any more fuses. Seems I can't follow a wiring diagram for the first 8 times I look at it...meh.
    I have already built and installed a wiring harness. Built the grid charger/discharger into an old xbox one case as I didn't have anything else to hand but had to put the fan on the outside of the case due to lack of space. I hope it will still cool it enough. Will do some more testing before I finally get round to getting my battery sorted. Fingers crossed!
     
    alftoy likes this.
  12. Vickstew

    Vickstew Junior Member

    Joined:
    Sep 14, 2022
    16
    9
    0
    Location:
    kirkliston
    Vehicle:
    2010 Prius
    Model:
    N/A
    20220919_222256.jpg 20220919_222058.jpg 20220919_222210.jpg 20220919_222419.jpg
    This is my build. Kids call it the flux capacitor :)
    All tests fine. Now to find a few days where mum's taxi isn't needed.
    Doing this as I have a gen 3 prius. 2009 plate as it was an import. Battery health is 50% and is occasionally throwing up the red triangle which I can reset with the Dr.Prius app. Just don't want to get to the point where it fails!

    So glad I came across prius chat. Loads of info here and some very knowledgable people around.
     
    Dxta, SFO and alftoy like this.
  13. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,132
    506
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    Notice you have the Meanwell 12 volt PS for powering the HV battery fan. It was noted that Meanwell PS wasn't sufficient to run the battery fan, better to convert an old computer AT power supply to output 12V.

    Hack an old ATX computer power supply for 12V
     
    Vickstew likes this.
  14. Vickstew

    Vickstew Junior Member

    Joined:
    Sep 14, 2022
    16
    9
    0
    Location:
    kirkliston
    Vehicle:
    2010 Prius
    Model:
    N/A
    I must have missed that important bit of info ‍♀️ Haven't had a chance to hook mine up yet to test it but if it doesn't work I have few old pc power supplies kicking around I can use. Will def check that out and let you know how it goes.
    Thanks so much again.
     
  15. Dxta

    Dxta Senior Member

    Joined:
    Nov 7, 2016
    1,932
    766
    0
    Location:
    Lagos
    Vehicle:
    2008 Prius
    Model:
    II
    Hi. Nice build. Initially, thought was an electric cooker(stove), from the build.
    What are the wattages on those filament bulbs you used as a discharger?
     
    Vickstew likes this.
  16. Vickstew

    Vickstew Junior Member

    Joined:
    Sep 14, 2022
    16
    9
    0
    Location:
    kirkliston
    Vehicle:
    2010 Prius
    Model:
    N/A
    Hey Dxta. Thanks. Still not got round to hooking it up to the car yet...busy bee. Those are 60W bulbs. I have 40W and 20W bulbs here too.
     
  17. Vickstew

    Vickstew Junior Member

    Joined:
    Sep 14, 2022
    16
    9
    0
    Location:
    kirkliston
    Vehicle:
    2010 Prius
    Model:
    N/A
    I have now converted an old pc power supply unit just like on the link you sent but was wondering if I could also use that to power the whole build if I wired it up to the AC input socket?
     
  18. alftoy

    alftoy Senior Member

    Joined:
    Mar 16, 2009
    1,132
    506
    0
    Location:
    Saskatchewan, Canada
    Vehicle:
    2008 Prius
    Model:
    Base
    Isn't your above build set up with ac in? Just use the pc/ps for the fan.
     
    Vickstew likes this.
  19. Vickstew

    Vickstew Junior Member

    Joined:
    Sep 14, 2022
    16
    9
    0
    Location:
    kirkliston
    Vehicle:
    2010 Prius
    Model:
    N/A
    Well I would do but when I attached my build to the car it went POP! Seems stuff was too close together and shorted something out. Decided to rebuild from scratch into an old pc case I had. Much more space. Putting the discharge bulbs directly wired inside too with an on/off switch for them. Did this last night so still to finish it off and test the voltages etc. 20221018_222002.jpg 20221018_221937.jpg 20221018_221919.jpg 20221018_221911.jpg 20221018_221903.jpg 20221018_221833.jpg 20221018_221826.jpg
     
  20. Dxta

    Dxta Senior Member

    Joined:
    Nov 7, 2016
    1,932
    766
    0
    Location:
    Lagos
    Vehicle:
    2008 Prius
    Model:
    II
    Nice one here. I'm also doing the same thing here, trying to get a separate switch that control charging the pack, and control also the discharging of the pack.
    I have wired the charger output to one section of an ON/OFF toggle switch, but I can't get to wire the discharge side to the other side of the switch.
     
    Vickstew likes this.