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Choosing a replacement module

Discussion in 'Gen 2 Prius Main Forum' started by RemiX, Jan 29, 2023.

  1. RemiX

    RemiX New Member

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    Hi! I've been studying the hell out of this forum for like the last 2 weeks after inadvertently buying a 08 Prius with the good 'ol triangle. I'm part way through reconditioning at deep cycle 3 using a CQ3 charger and a 65w headlight to help discharge/load test (did one before starting). All my modules started in the 7.9-7.94v range after sitting for 2 weeks before starting reconditioning, except for obvious baddy #10 who was at 6.59. Initial load test confirmed, and I bet the final one will too. Cool, now I'm looking for a replacement module.

    I went to 2ndlifebatteryllc as I've seen recommended by @PriusCamper. I'm thinking to myself: I've been seeing pretty steady self-discharge rates, and it seems to be known that the major self-discharge happens within 24h after full charge. I'm seeing modules that have been sitting for around 24hr, waiting between 2nd and 3rd cycle settle down around 8.2v. Cool, I see ebay listings tend to be advertising their voltage, so I'm still thinking to myself this must be what they measure to after that initial big self discharge and thus be a good indicator of health and a good way to match a replacement, right? Well, 2ndlifebatteryllc told me I really need to be matching capacities. Once again, I was using a spreadsheet I saw @PriusCamper post as a base as well as the info that hobby chargers just tell you how many mah they sent, not how much was actually taken in, thus not a good way to measure capacity, so I likewise didn't bother with recording that...

    I guess, ultimately this could be a PM to @PriusCamper just asking how he has/would choose a replacement module, but maybe as a public post this'll help someone one day like so many posts have helped me :)
     
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  2. Tombukt2

    Tombukt2 Senior Member

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    Cool stuff if you have the time and desire . Most folks gonna try n buy a . Is just faster and gets everybody back where they were before all this started for most folks that's a necessity getting to work and all that taking 24 hours or better amount of time to charge play and do whatever with their battery is generally not for most folks.
     
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  3. RemiX

    RemiX New Member

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    Sure, I get that. I happen to be between jobs right now so have more time than money, so it made sense to at least do some testing before just buying a pack or something
     
  4. TMR-JWAP

    TMR-JWAP Senior Member

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    If your pack is completely original and you're confident of how many modules you have that are weak, just purchase as many as you need and have them be in the 5500-5900 mAH range. That's a good safe range for someone that has the time to swap modules, but not the time to go through a bunch of test cycles on 28 modules.

    Please read the post in the below link:

    Inconsistent Hybrid battery readings | PriusChat
     
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  5. PriusCamper

    PriusCamper Senior Member

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    You're doing way better work than most who have journeyed down this path... If you can create a spreadsheet or something similar so we can see all your module data we could offer more advice... Enclosed is an example of a spreadsheet I created. It doesn't have to be like this one, but something similar would be useful.

    upload_2023-1-31_21-30-31.png
     
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  6. highmilesgarage

    highmilesgarage Active Member

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    I also bought my replacement modules from 2ndlifebattery, quick shipping and they worked amazing. I did it the lazy way using a grid charger and skip the reconditioning process which takes a lot of time.. if it fails I'm just going to do it again with replacement modules (that's the beauty of DIY) Me and my son have been driving it with no issues.

     
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  7. RemiX

    RemiX New Member

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    That's a great thread! Funny thing is when I first posted I was already at 3 cycles, just wasn't bothering to record capacity. I'm now following up with 4th and 5th cycles collecting that capacity data during discharge.

    Thanks, it's reading all those posts by guys like you, TMR and others that has helped. You can actually see how my spreadsheet is focused on voltage much like yours until the 3rd and 4th cycles. Still very much in progress, but have done modules from differing corners of the pack and seem to be getting 3600-5000 mAh.

    [​IMG]

    As much as I wanted to patronize Joe at 2ndlifebattery, this other guy on eBay "thehybriddoctor" accepted my offer for $54 for 4 modules ($74.76 out the door). And while I didn't get a response when asking about the capacities, it should be easy to beat some of my clearly old worn out modules - or get a refund if they're just bad modules. And spending under 100 is something I can feel ok about 'to see' (plus I have layers of protection: eBay, PayPal, and my credit card).
     

    Attached Files:

    #7 RemiX, Feb 2, 2023
    Last edited: Feb 2, 2023
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