Dorman Battery Experiences

5/16/2019 update on the module cycling. This covers the initial discharge and seventeen follow-on full discharge/charge cycles.
566E and 502F are down for the count and will be cores.
It looks like we're coming to the end of the road for this experiment. Cycle 17 is rockin' the house. Cycle 18 dipped a bit, but not unexpected or significant at this point. I'm doing the evening cycle tonight but don't plan to start another one tomorrow morning. I think they're pretty much maxed out on the recovery and they are looking absolutely spectacular.!!.

Even 572E has caught up and exceeded most of the others.

I'll document the mornings results and then just leave the cooling fan running all day. I have plans for tomorrow evening, but sometime this weekend, I'll replace the 2 bad modules with some that match the rest in the pack and reassemble the battery. I'll throw it in the car for some testing.

I've highlighted "green" modules/capacities that have exceeded 5800 mAh.
The average capacity of these modules has significantly surpassed anything I would have guessed. Did I mention I'm impressed?

If a fellow DIYer was trying this with a single channel hobby charger (and assuming it's one with a 10 watt discharge instead of 5 watt) this would have taken over 166 days going 24 hours a day. A single 4 channel charger would still be sitting on almost 42 days worth of work.

80% of rated capacity would be ~5200mAh.
85% of rated capacity would be ~5525 mAh.
90% of rated capacity would be ~5850 mAh
95% of rated capacity would be ~6175 mAh

 

I thought deep reconditioning cycles shorten overall battery life. That’s a lot of cycles on one pack.
I wonder how long it will last. @jeff652 could add his expertise to the discussion.

 

Last cycle for this pack...the final three cycles are fairly tight. I'd like to think this can show what cycling is capable of doing. I WOULD NOT expect similar results from every pack. That's guaranteed not to happen. ....I'll rebuild the pack this weekend with a couple similar replacement modules and throw it in the car for testing when I have a chance.

 

Thsnks for the data, but it clearly needed those modules before all the conditioning.

Posted via the PriusChat mobile app.

 

This isn't a problem for me. I have 1000+ to choose from.

The two I selected as replacements are from the original HV battery from the black 2005 prius I purchased for my son last August. That battery had 4 bad modules, but the others tested very well. They had 8 cycles performed and then placed on a shelf. They've been sitting since September, so it's been over 7 months that they've been sitting. All 24 good modules were still within .05 volts when I checked them. I feel safe saying there are no self discharge problems with these modules.

I've already installed the two replacements and performed an initial discharge plus one full cycle on them:

227G1A02509B tested at 6864 mAh
227G2A02851B tested at 7015 mAh

using the same exact settings and methodology as I've been using for quite a longtime. I just started assembling the battery this evening. Pretty confident it's going to be a totally kicka** Gen 2 battery. I'm looking forward to installing and testing it. I currently have a Gen 2 battery in my car that was built with July 2015 date code modules. That battery was built very recently and was in my car for testing. That battery will be going up for sale shortly. Will be interesting to see how this 2003/2005 module battery will compare. These are some pretty good "old" modules.

 

Ok

Posted via the PriusChat mobile app.

 

This drop in capacity and then subsequent breaking loose of the dam is something new I learned - that I could not have figured out by myself for sure. Does this also mean that if we are able to perform a 6+ cycle reconditioning using Hybrid Automotive's equipment, that would give much better results compared to the 3 cycle that most of us do? In the spreadsheet you have provided for these cells, which cycle shows this drop pattern you explain above?

I'm asking as I am putting on about 25k miles/year on a 2010 HiHy I bought last Jan which currently is at 193k miles. If 6+ cycles can really give a much higher level of benefit, then it may be worth a try.

Also, what is your experience that once you have restored these 10+ year old cells to pretty much 90+ of their original capacity, how long do these hold on to these higher capacities - I mean, after being built into a pack and used in a vehicle?

Thanks a lot for all the useful information several of you share on this forum. I am learning quite a bit but many-a-times it gets too techy for me

Hare Krishna!

 

@TMR-JWAP
Waiting for light to be shed on my question... TIA - thanks in advance.

Hare Krishna!

 

Why would you expect a response for a question about a Highlander in a Gen2 Prius website?

 

How are my below quoted questions specific to Highlander? I am asking about the principles and experiences of experienced folks regarding how long such well refurbished modules would last before losing capacity again?

Hare Krishna!

 

Hey, I apologize for not getting back on this. I remember reading the post, but life got busy and it slipped by. I'm just now getting ready to leave work today and the wife has a lot of my evening and tomorrow planned for me. I'll get some spread sheets up from other batteries that show this jump. I'm pretty sure I mentioned somewhere in the above thread that I was surprised it wasn't showing up. I'll get something up as soon as I can. Just bear with me a bit.

 

Perhaps because they were too lazy to use this forum?
Toyota Hybrids | PriusChat

 

Do not do extra cycles on your modules. More than 3 yields diminishing returns and your modules have a statistical limited life in full cycles. It is also unlikely to get back to 90% capacity in an older module. Module capacity is specified as 6.5 amp-hours at 1C drain rate. Since our hobby chargers operate at a lower drain rate, they overstate the achieved capacity.

JeffD

Posted via the PriusChat mobile app.

 

It wasn't a question specific to a Highlander, it was a question about reconditioning a Toyota hybrid battery - which is the subject of this thread. It just happens to be in the gen 2 section, even though those battery modules could be installed in or originating from a host of different Toyota/Lexus hybrids.

I get that people should post in the correct locations, and I support that motion. However, it can be more diplomatically conveyed when it needs to be.

Thanks for all your work @TMR-JWAP I think it's super cool that this battery will see further service. I'm curious to see how long it will last!

 

Would the 'extra cycles' statement also apply with the less intense 5.8v discharge cycles that @TMR-JWAP is doing ?

Since he is using a fairly high end hobby charger (though I could be wrong), can we assume that the observed capacity is close?

 

Beware!!!! Dorman uses Gen1.5 cells in 2004-2009 Prius rebuilds!!!
Beware Dorman Hybrid Battery Replacements use 1st gen cells!!! | PriusChat

 

Duh!

It probably doesn't matter which generation module they use, as they are all old. The exception being modules 5 yo or less.

I doubt the pool of modules from which Dorman has to pull modules contains these newer modules.

 

I understand the Gen 1.5 modules were especially bad.
I know Toyota said they are using a higher grade of Nickel in the Gen 4 Ni-MH modules.

 

On another note, I no longer use my Green 2007 for testing batteries, so this pack is STILL installed in my car and running like a champ. Current tank is around 360 miles and 51.1 mpg. All my testing is now done in my 2005 or 2006 back-up Gen 2.

As for testing at 1C or not. It's irrelevant for me. Why you ask? I've explained it a few times previously, but I'll do it again.

I have a tremendous amount of individual module data from charge/discharge cycles of Gen 1, Gen 2, Gen 3 and Gen 4 packs.

This includes virgin Toyota OEM replacement packs, one year old low mileage Toyota replacement packs, 5k-20k mile Gen 4 packs and even 17 year old Gen 2 modules and everything in between.

The test methodology is the same for every test.
The new Toyota packs and newish Gen 4 packs provide the "standard" for comparison. That data becomes the "Holy Grail standard".

Every other pack and module is tested using the same exact procedure. The results can be compared to the "Holy Grail standard" to see how well the "old" pack/modules measure up.

Can I test at 1C? Absolutely. I have a programmable electronic load that can maintain a constant current load. (I think I have a thread on here somewhere that has a module being discharged at 1C and shows the points where each individual cell depletes.) Unfortunately, it would require testing one module at a time. I don't have enough hours in the day to do a one hour test on every module. But, I do use it to apply a short 50 amp load to every module to verify they don't have some underlying issue that doesn't show up under low current.

Sometimes every module in an old pack will test out in the 4000mAh range. More frequently than I ever would have expected, I'm finding packs where they're averaging 6000+.

So, are there darn good modules out there? Absolutely, but you need to have to have a good selection of cores and the equipment to test/find them.