Gen II Prius Individual Battery Module Replacement

Now that it's done you better do something cool on that channel like blow stuff up so it was worth reading all those vote for me posts in here.

 

The thought I had in mind when compiling Health and Safety page on my site was:
- making the video of how dangerous transportation of Prius modules could be, especially via Airmail.

I.e. If battery poles from NP2 module could protrude through poor packaging and touch metal case in the luggage compartment - that could melt the whole thing :-(.

Is that something you would like to see? i.e. NP2 Prismatic Prius module (as if it was prepared by clueless eBay seller for delivery) being put into the metal can, accidently touches the metal surface and SPARK! That kind of safety video is doable...

 

Lipos might be more fun but here's a couple of ideas:

• Try driving a nail through the side of one of the cells (electrode to electrode)
• Try to massively overcharge one without support (preferably one with a blocked vent)
• Try arc welding metal with a few of them in series (might actually be handy for the trail)

I'm sure there's alot more if you want to be creative and actually get some followers

 

1) Can't think about real life situation where something like that could've happen. Your suggestion for the title e.g: "Nailed It" or perhaps "Nailing NickEl"?
2) That has been done so many times on Youtube - not even cool any more. Everyone knows they have to be compressed while charge.
3) I see practicality in that one (safety issue) - i.e. if you use non isolated socket without extender - you can easily touch 5 modules in series. Comn'on, confess - who did that at least once ?

 

I agree #2 is a bit boring but #1 would be more fun.......couldn't you just call that "Nailed in transit?"

I would still really like to see someone create a portable arc/TIG welder from a few of these. I know people create them from an old alternator and this would be great because it's totally trail portable.

 

I've done once welder from transformer out of microwave owen with rewired secondary (making it 2 Volts) and timing controlled by IC.
Too weak - not enough current - only good for very thin metal. Prius modules could deliver high currents but using them for that is unsafe IMO.

 

I was thinking something like this (but with NiMH modules):

Weld Anywhere Lithium Battery Powered Portable Spool Gun Arc Welder | eBay

 

I picked up an old Gen 1 battery from a used car lot when I bought a car there. The owner was quite enthusiastic about electric and hybrid cars. He gave me this old battery that had been out of a car for I don't know how long, but I think it has been several months at least. I have been working with the first 4 batteries for about 3 days. Here are my results after 6 cycles on each battery.

View attachment 98368

I am charging at 2 amps, discharging at 0.7 amps down to 5.4 volts. I am using the Hitec x4 80. Should I abandon these batteries? Any ideas? View attachment 98368

 

Your attachments aren't coming through so please post up your results again so we can have a look.

I would only be discharging them down to 6 volts myself though unless this is just a pack for experimentation.

 

Re:

• multiple cycles - too little to slow;
• insulation material or is it?

To contribute to the thread: quite a while I've got a "dead" 28-module pack with 8 still good and 20 - completely depleted to zero volts. (Controller was dead, wires - completely corroded). Initial charge-discharge showed very low capacity <1Ah.
Connected those 20 in series in cradle and they have undergone quite a few cycles of charging / discharging to test new builds of 20 and 19-channel Analysers, new compact 6.3A Load and most recent design of the Charger for 17 modules (1/2 of Camry). Rejuvenation of those modules was not a goal. Just something to test my gear.
Was discharging at about 6 Amps and charging at about 1 - 1.4Amps. I have not discharged them below 6V and have not overcharged (as amount of charge and temperatures were controlled by the Analyser).
Observation: being connected in series with the same chanrge/discharge current being applied to all - modules are very gradually but unevenly gaining charge with 4 out of 20 still looking bad and 16 now at about 2AH which is still not good enough for being used in a car IMO.
Verdict: for any commercial application - that would be waste of time. For DIY - perhaps there could be a hope. I have 4 compact loads and few chargers in the development pipeline - hence those modules will be used even further - will see if they will raise a bit more in capacity (or die completely).

P.S. Unexpected smoke came out of the newly built model charger on Saturday. Double checked all circuitry - no mistakes. Who would have known that recycled plastic from Toyota which I used as a temporary isolator was painted from one side with the black mettalised paint (perhaps for RF shielding of the electronics) and have created unexpected shortcut via the bolt and nut :-(
Changed plastic to one from Sony - all good.
That is a safety reminder to all DIY people who use whatever material comes handy - check the insulation with the megger first! Remember that concrete floor is electroconductive - hence "touching one Live pole with one hand" may not be safe. Use RCD devices. Use insulating pad under the pack. Use Electrical Gloves.
Play safe!

 

Getting back to work---- or play.. I am using HitecX4 Plus to condition my 06 Prius battery's (188,000) miles. A few weeks ago I replaced 5 modules that showed less than 7 volts to get the car running. Since then I've been educated by this forum, and have been schooled by this thread, may it last a long time. As I ran several manual discharges and charges on a few extra ebay purchases I find what has been talked about previously to be true about the quality of modules. A few were border line usable and others were much better.
I recorded voltage before load test, (load 120w for 75 seconds) and after with drops about .5 volt on some. I connected mu HiTecx4 Plus and started DC/CHG x3 and one came up DRY, there is no reference to this error code in the manual and shut down automatically. I would guess this module is history or is there hope to rehydrate?

 

.

 

X2

When it says "DRY" on the screen, it is the wait time between a charge or discharge cycle. Basically it's the waste time that is set. You can set the WASTE TIME value inside of the USER SET PROGRAM menu. It doesn't indicate anything about the condition of the batteries at all.

 

I have been following this site for some months now - since my 2006 Prius developed battery problems - with all the attendant warning lights. I live in Johannesburg, South Africa and I tried to get some battery modules locally but cold not source any. I put an advert on various websites but only got responses from people like myself - who had a Prius with a problem (or who anticipated such a problem shortly).
I am not exactly sure how to enter the debate - but I need some help and I am going to try posting this and then I will try and describe my problem (if this appears to be the way to enter the discussion)

I eventually managed to source a second hand battery with all 28 modules - from a scrap dealer who dealt in Toyota "2nd hand parts"
I had originally intended to try and refurbish and rebalance all the modules I was going to put into my car - following the excellent advice posted by many of you on this site (thanks to "ryousideways" for starting all this!). As I had purchased a battery from a 2007 Prius - that I was assured had been sitting in the scrap yard for about 18 months - I decided to just try and install it 'as is' into my car.
It did not have a CPU and the connecting bits, so I took those from my battery and put them into it and used my case as it was in better shape than that of the scrap yard battery.
I put it all back together (thanks to all your advice on this site) and put it back in and held my breath while switching it on.
To my absolute surprise it started (after some initial ticks and clicks and after refusing to go into gear) and all the warning lights went off! I was elated and surprised.
I put my car back together and decided to hope for the best. In the interim I supplied some of the other guys who had contacted me with their own problems with some of the cells from my battery - but warned them about all the caveats on the site and the need to balance etc etc
This is the good news - but 4 months later (about a week ago) - the warning lights came back on!

I took the battery out again and rechecked the voltage on each module - and discovered that one of them (the one that the orange power cord is attached to) had dropped in voltage to around 6V - all the rest were still at around 8.
I decided to replace it with one from my old battery - which was still at around 7.3V (at that point I had not really absorbed some of your advice re testing them 'under load' - which I now see - having re-read a lot of the posts on the site). I put the battery together again and put it back into my Prius - without putting all the panelling back.
I tired to start it but it would not start. The power came on and the lights all came on - but the 'ready' light on the dashboard would not stay on - it flickered on and off and then stayed off.
I rechecked the orange safety fuse - and it seemed as if it had not clicked down properly so I removed it and reinserted it firmly.
Still no change. I took it our and checked it for continuity between the two connecting pins (in case the fuse had blown) but it gave me a reading re the resistance - indicating continuity.
I am a bit stuck as to what to try next - someone said 'maybe the CPU board has blown' - but how? why?

Can anyone help me as I am at a loss as to what to try next? In South Africa it is not easy to find the kind of equipment you guys are using to read the codes and reset them etc. I am thinking of ordering one of them via Amazon if nothing else transpires?

 

I am going to post this here, since it seems this is sorta the thread to be doing it rather than start a new thread.

I am now in the process of reconditioning all of the battery modules in my pack from my 2007 Prius. As i go through and perform the DCHG/CHG X3 cycles, I am updating a spreadsheet on google docs, which can be found here:



The first tab shows the voltages of each module when I first pulled the pack and tested without load. The module reported by techstream a bad was number 20 (in bank 10) and only showed 6.38v. I initially tried to rehabilitate that one module with no success. The voltages were all over the place when attempting to charge/discharge it. I'm confident it is unsalvageable. My other initial concern was the modules at either end of the pack. They were a little lower than all others, but not too much so.

The second tab shows the results of each of the modules after three DCHG/CHG cycles on my HiTec X4 AC Plus. I am charging at 2.0A and discharging at .7A down to 6.0v. Maximum injection is 7350mAh. One module for now looked like a 4th cycle would help and it appears it did. I think that what I am seeing is good results thus far. As the modules progress through each cycle, I am seeing an increase in capacity so I think I am on the right track If someone could offer some advice/perspective, it would be appreciated.

And lastly, once I am done charging modules, I am a little fuzzy on the final steps needed. I think I read that I should be discharging using a load such as a headlamp bulb, while measuring voltage, to bring all of the modules down to about 7.6v. Is this correct? Anything else I am missing?

Thanks

 

Each cell in a module is 1.2 V (nominally), so the nominal voltage of each module is 7.2 V (as each module is made up of 6 cells. So, if you have a module that is 1.2 V less than the others, then it is usually one indicator that a cell has gone bad - usually a reversed or shorted cell. There is nothing you can do to revive a module in this condition.

The first thing you should have done after taking the initial cell voltage readings was to load test each of the modules and record the results. This can be done by using a headlamp with both the low and high beams wired in parallel. You record the starting voltage and apply the load for say 60-120 sec (or longer, you decide how long but it must always be the same for all modules) and the record the module voltage after the elapsed time (with the load still applied) and then remove the load. A good cell will then bounce back to almost the starting voltage. The good thing this test shows is weak modules. Weak modules drain quickly, and also charge quickly. The important metric is the difference between the end voltage and the starting voltage (the smaller the difference, the better). When you compare this difference across modules, the bad ones will stand out.

The other test that is important is self discharge. To do this, you need to measure and record the standing voltage, and then leave the module idle for 2-4 weeks (the longer the better). At the end of the idle period, again measure and record the voltages. Compare the differences between the end and starting voltages across your set of modules (again, the smaller the difference, the better). Good modules will have a very small difference.

You can still (and should) do both these tests.

Once you have performed both these tests, you can the select (hopefully) 28 good modules to rebuild your pack. Charge the up to 80% and then discharge them so they are all the same voltage, +/- 0.3 V.

Hope this helps, and I'm sure some of the more experienced people on here will pick up any errors or add any missed info.

Good luck with your endeavors.

 

Mike, 2 things you should be doing that are both cheap and easy to do is to load test all the modules (headlight, stopwatch and voltmeter) and then balance them before install (connect the battery in parallel to equalize all the voltages). I would also make sure your 12V battery is in good shape too (load test).

 

Are those voltages normal during 1st charge cycle? Every setting is as decribed is post 18,

 

I was seeing roughly the same thing with my X4 Plus A/C. Voltage would usually peak at about 8.7v during charging. It will come down naturally when charging is done, as the surface charge will dissipate rather quickly and leave you somewhere around 7.9-8.0v. At least, that has been my experience.