Is adding a second battery possible?

Discussion in 'Prius PHEV Plug-In Modifications' started by hyp3rmil3r, Dec 22, 2019.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Using a pool water pH test kit, I only found KOH around the terminals and nothing in the pressure relief tubes tested.

    Bob Wilson
     
  2. T1 Terry

    T1 Terry Active Member

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    Thanks Bob, so the pressure build up was enough to force the KOH out through the terminal seals ..... that was my original guess. If the relief valve had worked to release the excess pressure then there would have been signs of KOH in the vent tubes as well ,,,, the escaping gasses would have carried some vapour with them.

    I guess my first piece of investigative work will be to cut the valve out of a stuffed module so I can see just how it is constructed and see if I can use this as my access point to bother deliver the KOH as well as the gas vent. I think I could make a connection that would hold 80 psi, but I think I might drop that to around 50 psi and see what affect that has on charging rate v gassing.

    T1 Terry
     
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  3. bwilson4web

    bwilson4web BMW i3 and Model 3

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    I had noticed one of the two terminals ran hotter during charge/discharge. My hypothesis is the heat softened the "O" ring and plastic enough that it released first. I too endorse using the vent tube for adding water AND some form of external pressure control and/or gas recovery.

    Speculation, some form of external gas holder like a cylinder with a couple of CCs of space clamped to the pressure relief vent. The extra volume will reduce peak pressure and mitigate some of the gas loss through the weakened seal. Some experimentation will be needed.

    GOOD LUCK!

    Bob Wilson
     
  4. sam spade 2

    sam spade 2 Senior Member

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    Well that is just short sighted and stupid on it's face.
    Caustic solutions can be just as dangerous as acid ones.

    Adding a caustic solution to another unknown solution is almost NEVER a good thing for a "novice" to be doing.

    And just because you haven't personally seen the results of all the hairbrained things that have been tried over the years does not mean that they haven't happened.

    But if you enjoy tinkering with things like this, more power to you.
    My fear is that someone with ZERO knowledge and close to zero common sense will embark upon an "experiment" of their own and end up with a disaster. That happens all the time.
     
    #44 sam spade 2, Nov 24, 2021
    Last edited: Nov 24, 2021
  5. vvillovv

    vvillovv Senior Member

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    Some of my more sensitive ginger friends would not be amused at the reference to their gender, I'm pretty sure. Might not even like that I liked your post, either. Oy!
     
  6. T1 Terry

    T1 Terry Active Member

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    Wow, I thought it was only the Ozzie forums that attacked from the sidelines ..... the actual ratio of KOH to water isn't like it would be flesh eating or something, but if the joints weren't secure then there would be quite a bit of the solution would leak out due to the pressure involved.

    As for someone who didn't know what they were doing tackling a project like this ... it simply wouldn't happen, I'm not producing a step by step process to do the upgrade so I doubt they'd even be able to get the original battery out without zapping themselves ... the 200 plus volts DC certainly hurts enough to let them know they've done something dumb, if they continue after the first zap then Darwinism will most likely come into play and remove them from the gene pool .....

    T1 Terry
     
  7. sam spade 2

    sam spade 2 Senior Member

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    That theory is only valid up to the point where the gene pool is SATURATED with morons.
    As each day passes, it looks more and more like we have passed that point already.
     
  8. T1 Terry

    T1 Terry Active Member

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    common sense.jpeg


    T1 Terry
     
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  9. bisco

    bisco cookie crumbler

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    'ignore' is your friend :)
     
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