okay I’ll try to fix them and hoping to see some result.

Thank you!

 

Hi guys could you please help me as I'm confused now
I have Honda civic 2007 and trying to recycle cells which are in my opinion in not as bad state
each double pack (12cells) holds between 14.8-15.8v (middle ones the least)

Now I can't take them apart to split doubles as I don't have a way to solder them back so have to charge each double pack
I've set initial numbers to
charge @5A
discharge @ 1A
cut off V @ ?
timer to 148min
cut off peak @ 5mV
capacity @ 11000mah

Could you please confirm those values and tell me what should be cut off V as I'm not sure, I believe 1Vxeach cell so 12V would be too low ?
should I then set it to 14,5V ?
Should I adjust any other values ?
Also should I just connect them to ends on plus and minus or any other way ? (I'm using imax b6)

 

Can someone please tell me where to hook up the wires for my bulb discharger?

 

Same place you hooked your grid charger.

 

Hi S. Keith, I would like to say thank you for providing lots of knowledge about the IMA battery. It helped me successfully recondition my bad IMA battery.

Here is the story:
I bought a second-hand honda civic hyrid 2007 last year. After driving for 1.5 years, the IMA light was on. I tried many times of 12V reset but the IMA light came back soon. Then I looked for many possible options and decided to go for the DIY grid charging solution.

I did learn a lot about circuit knowledge before but I forget most of it. I started to learn everything about IMA battery and found the EVF here is the best place for me. I viewed the discussion about IMA publised from 2013 to 2022, and found your ideas are really helpful.

Here are what I did for my IMA battery :
I removed the IMA battery out off the car.
DIY a grid charger, and charged the battery 24 hours to full at 186V.
Used 40w + 60w bulbs in parallel to discharge the battery to 8.5V
Charged it for 24 hours to full at 190V.
Discharged it to 180V, and installed back to the car.

I justed finished it, and drived it for about 60KM. Of course the IMA light was off. The battery is much better than before. It never droped lower than 6 bars, so no recalibration during the driving. I can tell that the charing (when braking/sliding) is far more efficient than before. Today is the first day after the reconditioning. I am very happy with it, but will keep testing in the coming weeks.

Thanks again.
And I also would like to thank EVF, and anyone contributing to EVF.

 

Glad it's working.

I've been where you are. Hopefully in your case, it holds out. My initial results were spectacular, but about 9 months later, the whole pack went south.

In the future avoid discharges below 66V. They really don't buy you anything, and deep discharges can push a marginal cell into full failure rendering the pack unusable.

 

OK! That's a good point! Will not drain it below 66V again. Thanks for the further suggestions.

I will update my result in several months.

 

Once you experience a recalibration, it's time for another grid charge. A discharge is not likely necessary unless it's been awhile.

 

Thanks so much for this post. It has been the backbone of my decision to balance my own 2007 Civic Hybrid Battery, describing the whole process very nicely.

For anyone else following along, I recommend this excellent video of the process of taking apart the battery which I followed without difficulty.
I am on the first round of discharge/charge right now. Here’s a photo of my setup. I’m using six imax B6 smartchargers with temperature probes.

I’ve downloaded your spreadsheet and am using it to input my own data.


My setup for balancing NiMH Hybrid batteries using imax B6 clones.

 

I'm so sorry. There are so many better references than this in so many places. The B6 are just a **** show.

The ONLY thing working in your favor is you likely have a CA3 pack. The sticks in the CA3 pack were notably better than the originals and the CA2 sticks. Regardless, you would be done faster and get better results doing a whole-pack grid charge/discharge solution rather than using those cobalt blue turds.

Did you actually sack up and buy the genuine SkyRC Imax B6, or did you buy the cheap Chinese clones? If clones, be ready for inconsistent performance and potential erratic behavior, especially with undercharging.

Rather than cycling, I recommend the following:

Charge to dV termination with cooling. Sticks should be comfortably warm to the touch.
Wait 5 minutes with cooling
Discharge each stick to 6V at the maximum current the B6 will permit - 0.7-.8A typically. Record mAh
Discharge to 2.4V @ 0.4A. Record mAh.
Charge at 0.4A until over 6V, then charge at max to dV. Set aside.

Repeat 21 more times.

Optional:
Discharge each one to 6V. It should be proportional to the original to 6V + the discharge to 2.4V. There is some unusable capacity in there, and it varies, but it's on the order of 500-1000mAh.
Charge each stick to dV cut off with cooling.

Assemble pack.
Before you install the junction board, charge each PAIR to dV cut off with cooling.

Good luck.