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Has anyone replaced the cells in a module for a Gen2?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by PriusThatTows, Feb 7, 2024.

  1. PriusThatTows

    PriusThatTows Junior Member

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    I am having trouble researching this because 99% of the internet related to prius modules uses "cells" interchangeably with "modules". I am talking about wanting to replace one or all of the 6 cells within a single module of the traction battery. The reason I'm not wanting to just buy a second hand module is that I can't find any above 4500mAh, and the rest of the battery is in fantastic shape with all modules exceeding 6500mAh. So if I could order replacement cells... well you get it. Can this be done? Thank you!
     
  2. PriusCamper

    PriusCamper Senior Member

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    There's 168 cells in a standard Prius battery pack... There's 6 cells in each module. There's 28 modules and 14 blocks in a pack. And yes, finding a high quality replacement module is not easy because there's so much untested junk out there. But this guy teaches hybrid & EV at the local college and has spent more than $20K on lab grade testing gear several times since he first started. His used spare modules are always the best you can buy: Hybrid Car Battery Distributor | Contact Us | 2nd Life Battery
     
  3. Tombukt2

    Tombukt2 Senior Member

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    So what is the deal We can't get the original modules like the Toyota has the market cornered No one else can buy them or something? Aren't these like Panasonic if I'm not mistaken or something along those lines. I'm just not knowledgeable in all these battery pieces but I'm shocked that somebody hasn't come up with a way to just pretty much whack together any voltage battery pack you want pretty much I mean 400 volts 600 220 whatever whatever kind of chemistry I don't really care about all that just need it to work as a battery you know maybe fit in some sort of a case of some fact simile to the original or I can put it kind of on the original tray it sat on in the car etc I mean it doesn't have to be exact a little bigger would be okay actually I just find it hard to imagine that this this cat hasn't been skinned yet but I guess maybe battery tech is not there for the experience DIY or something.
     
  4. PriusCamper

    PriusCamper Senior Member

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    Multinational corporations aren't in the business of making things easy, they're in the business of maximizing their monopolistic intentions as much as possible to make things as expensive/profitable as possible. This dishonest racket when it comes to NiMH battery chemistry is the reason why every other auto maker moved on and won't have anything to do with NIMH. Even Panasonic themselves is focused on moving on from Toyota and working with other automakers more interested in advancing battery technology than being an overpriced stick in the mud like Toyota's super heavy and not practical for EV monopoly on NiMH.
     
  5. pasadena_commut

    pasadena_commut Senior Member

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    Not just Toyota. The NiMH sticks in the Honda Civic Hybrids could also not be purchased from the original manufacturer. Eventually Chinese made sticks which were theoretically the same became available, but the quality was very hit and miss. Only a company that did a lot of business rebuilding batteries (like BumbleBee) had much of a shot at "getting the good stuff".
     
  6. PriusCamper

    PriusCamper Senior Member

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    Yes... The NiMH sticks were an earlier design before the superior Prism prius modules came out, so it would make sense that aftermarket knocks off are more established than aftermarket Prism modules, which you can get from China, but quality is awful, at least from what I've experienced.
     
  7. Brian1954

    Brian1954 Senior Member

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    Almost anything can be done if you have enough time and money, but I do not think it makes any sense to try to do this.
     
  8. PriusCamper

    PriusCamper Senior Member

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    It comes down to what you can afford... And usually the best and most lasting results come from replacing the first module with things getting to be a more often recurring hassle with each successive module.

    But if you have basic auto repair skills and an empty bank account, replacing a module will only cost you $40 and a bit of time.
     
  9. Brian1954

    Brian1954 Senior Member

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    The OP is talking about replacing a cell within the module, not about replacing a module in the complete battery pack. Read post #1 again.
     
  10. mr_guy_mann

    mr_guy_mann Senior Member

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    I really don't think that's even remotely practical.

    It would be like cutting apart a car's 12V battery to replace a cell. Very messy and unlikely to work, but (in theory) possible?

    Posted via the PriusChat mobile app.
     
  11. pasadena_commut

    pasadena_commut Senior Member

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    More possible for a conventional 12V car battery I think. There all you need to do is get the lead plates out, clean them up (or replace them), and put them back in. It needs straight sulfuric acid, not some proprietary electrolyte. For instance, in S1 E3 of "The Last of Us" the character "Bill" keeps a disassembled truck battery in a fridge, with bottles of sulfuric acid to complete the assembly.

    I have no idea where one would get electrodes for a NiMH battery, unlike 12V lead acid batteries, where the plates are just lead. Similarly, for a lead acid battery just add sulfuric acid (readily available). For the NiMH KOH electrolyte would be a start, but at what concentration, and with what other additives?

    I think about the only thing one can reasonably do at the cell level on a Prius module is add distilled water. And that isn't really cell specific since that can (and will) move between the cells. Plus closing the holes in the plastic afterward is not trivial. A better description might be "extremely challenging". There is a whole long thread on this in the technology forum.
     
  12. PriusCamper

    PriusCamper Senior Member

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    Yeah... That's never been possible, so it's not even worth addressing... A couple people on here in past couple decades have experimented with rehydrating recipes with modules, but if you have a bad cell the module is bad and there is no way to repair it. However, Lithium upgrade companies for hybrid cars may have the potential to replace individual cells in their modules/pack in the future.