How to test if individual battery modules are good

What do you look for? Say you have the triangle of death pop up and go through your pack module by module, and 1 just happened to go out certainly. But how can you tell if the others would be a viable candidate to go back in the pack?

Also, id say theres different kinds of viable candidates. Some that maybe would last you quite a while, then theres some that some may say is viable that might not last as long.

Is there a certain number of things to check out before you decide to put a module back into a battery pack? I want to find out what things i need to look out for for a "healthy" pack once I get done. What tests do I need to do on the modules to see if they would make for a somewhere in the middle. Lets just give some general numbers here. Say a battery pack nominally lasts 180k miles. Say one just happens to crap out at 80k miles on you. What tests should I perform and what would tell me what these numbers are?

See, what I'm doing is the tests procedures I saw on one video

Ok, so what am I getting from doing this procedure he shows?

From what I've been seeing, his tests, which I dont know what it tells me about these packs if their subpar, or high grade, Is; using his procedure, I'm trying to find packs that can get up to a 5000mah Discharge capacity.

But ok i see but i dont understand. What if its taking me 20 runs to get a pack to get up to that value? What if so far none havent not been able to get up to that number, but some take a slow amount of time to get up there? Out of all the ones that pass this procedure, which are subnominal and which are high grade? Is there more tests I can perform?

I've heard of a load test. Take and put a 5amp load on the modules, after theyve been ran through the previuos procedure, and time how long they take to drop their voltage. Some peop;le just go by amount of speed. Some people do a 1 line test and see what it drops to after a set amount of time. Then theres people, like for example

where he records how long it takes to reach certain voltage numbers between modules. He mentions that certain voltages between say 7.0 and 6.5v are more imprortant than the time it takes to drop between 8.0 to 7.5. What would be the logic behind this? WHy would the numbers he gives for importance of holding voltage during a load be more important than the other numbers? is that just how (these) batteries are? Or what voltage does the Prius begin to set the pack back to charging mode, instead of discharging in the car? If its 6.5v i could see what he's saying. but if its say 7v, but Idk. :What numbers are the most important/voltages to check for load voltage drop?

Then theres another test I saw. Finding the internal resistance. This guy does it with a battery tester, in this video

Also I was reading a topic here where someone was showing his Internal Resistance on his pack while it was in the car with the Dr. Prius app. Someone said that that IR number doesnt matter since the car doesnt have a load on it or a charging going on for those numbers. So, is there some way out of the car to do this, run a charge or discharge while testing for IR? Would that work with that battery tester shown in that video or would it cause the battery tester to mess or or messup maybe something in teh batteries?

So, what do i need to look for to find the good packs, and what numbers am i trying to get? Maybe just an average from all. Should I run all three of these things? What numbers would be bad, especially on that load voltage drop test. What about IR? would that video work fine to see if the module had a bad IR or do I need to have a load; charge/discharge either or, on it to run that test to get some valid information?

heres the thread were someone said the IR numbers from the dr prius app didnt matter unless there was a load on the car or discharge 2006 Battery internal resistance | PriusChat
maybe tho the deal with there is that its because the battery is put together in series in the pack. running in the car. would a battery tester like in that video work to find bad IR?

Or .. would that procedure to charge back up the pack out of the car like in the first video, suffice? I just think that maybe some of the packs can get the capacity back in them, but i dont know im just making this up myself because i dont know one way or the other, you can get the capacity back ijn them, but then they would drop that quickly, or maybe the charge doesnt get it back up enough to allow it to reach a discharge capacity again. Important thing here is, I dont know how that procedure/test works. Im just seeing numbers and not understanding anything.

 

ive read a little bit of that. 130 pages.
Im just asking for a quick tip on how to tell whats good whats bad from what ive heard. how do i know they won't just flop out, from the video i was watching example. it says; "charge them up to 5000mah discharge capacity". if they cant make it; bad. if they do; good. some of his doesn't make it. throws them away.
But what doesnt make any sense to me, is he doesnt say why he decided to throw away and replace a couple others. Ones that even reached 5000mah discharge capacity.

so im clueless. i dont want some that will wear down on me and go out within 2 weeks of doing all this and wear down all the batteries i charged up. this has took me 3 weeks to do with a 4x charger. at 1A discharge. you know, at searching for a 5000mah discharge capacity everytime it moves up a little bit on its way to 5000mah, that 5000mah takes 5 Hours do do.

The only other thing Ive heard is, that other video I linked, showing using a battery internal resistance health tester. toss away high IR ones.

But is there any thing here that people have had to figured out while working on these, that tells you that you can do a test with, that will tell me my battery module is going to be healthy for a nominal, another 100k more miles. yea their old. IM not asking for any specific to mine; would be nice, but just some general information. Or does everyone want to keep that hidden.

Come on, give some tips without me having to read 130 pages of posts that some of them doesn't make any sense for someone to refurbish their own battery.

Lot of people like to say, oh this isn't any good. just buy a new battery pack. ok yea sure. Then i watched a video of some guy trying to refurbish his own, he gave up and ended up taking it to a shop, that within 5 days had the whole thing put back together and running just fine. don't know how long after he made the update video

Im thinking here about my battery specifically, its old, but its not worn out as its not be used a whole lot. Internal Resistance seems to be what i need to look for. Maybe if I can find some correlations to charge/discharge cycles and IR I may post them.

But can anyone give me any tips. Because if not, I'll just do my own write-up here eventually. Keep it to yourself if you want to but I'm going to let everyone know everything I can find out about it. If you cant do it, or dont have the means to do it, then pay someoen to do it. but for the rest of us, please be helpful.

 

Ok so I finally got them all to 5000+ discharge 7500 charge. the one bad, replaced with a brand new one. also tested it. its very good shape. charges quickly.

Now,l Ive read your supposed to balance them... by connecting all the postives together from all the modules together and letting it sit for 2 days. also i seen differntly to connect the negatives together, too. Which way is right? im sure positives but do i need to .. teear up another coat hanger to do this with?

how important is this and does it actually balance? what does it balance becuaes after doin gall the positives before with a battery i returned, after 2 days, they werent all the same Voltage. One was fairly higher. so it ddidnt seem like I did it right

 

what do you mean?

I just made up about charging quickly. i have no idea how long it took to charge. it took as long as any of the others to charge up.

I hear about the "matching capacity" or something like that in putting them back together in pairs. I have no idea what that means. 0. Nothing. SO i just flipped them inside out, while taking the new one and setting it in the dead middle.

How am I supposed to find equal batteries as my used one with all these "inserts ebay auctions descriptions - 7.8v battery. B-grade battery. 3000mah battery" None of this means anything except its not dead to almost nothing at all to 3000mah? mine are 5000+.

So, could you elaborate? Ive already spent a lot of time working on this, paying for this new cell, to hear its a bad idea. How?

Let me see if i got the idea. every time a cell fails a little bit, and from my charging with a hobby charger, this is the idea i get. Sometimes they would give me a 4000mah discharge, next run it would drop 400mah -3600mah. or between sets of 3 runs it would do that 400mah loss. but the next run it would go up to beyond where it was before it dropped. The only idea i can get is if you lose a little bit then it never comes back. ever. because the best one in the pack charges up before the others ever get fully charged.

But I think hows does that matter if the batteries better? Its going to keep up with discharge rates. And they should all eventually equalize after some runs to getting up more charged. They are all discharging. Even that brand new one, only gave me a 3000mah discharge capacity on its first run. They would all eventually drop like that if the car sat for a while.

Whats the big problem? I am really going to ignore this unless this is a big problem. I never hear anybody say this and give a full explanation.

I think from seeing this battery get run down from the bad battery, that they do get a low discharge capacity some of them do and do not want to come back up for quite a while. 1 even took 30 runs to get up to 5000+ but it got there. But one, out of the original battery, hit 4900 discharge capacity on the first run and hit charging capacity.
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What test are you talking about running? Are you talking about where they are in packs of 2? i put the new one with the one that got to 5000mah on its first run