I just recently purchased a 2006 HCH2 and am looking for some advice on grid charging/discharging the battery. I don't have any IMA lights or codes but have seen some recalibrations. My previous car was a G1 Insight so I'm familiar with the basics but am looking for some suggestions on what my target discharge voltage should be. Is it better to do multiple charge/discharge sessions or is one charge/discharge/charge enough? For the charger, I'm using the same Meanwell HLG-60H-C350A power supply that I used for the Insight. From what I've read it is compatible with the HCH2 battery. My discharger is a simple bulb discharger with two bulb sockets wired in series. I have 25 and 70 watt bulbs available.

I'm going to be charging and discharging the battery outside of the car until I can get a 12V power supply for the IPU fan. It looks like the air is pulled in from the single narrow slot at the top of the battery and through the two slots in the bottom. I'm going to be using a floor standing fan to cool the battery. Which end of the battery should the air be blowing into?

With my G1 Insight, I followed the advice of a forum member and performed a grid charge once per month and a discharge to 90V (don't remember exact value) followed by a balance charge every three months. This routine worked great and I didn't have any battery issues for the six years that I owned the car.

Thanks.

 

HCH2 fan is PWM controlled. It will not accept 12V and spin unless you ground the PWM wire to (-). This will cause it to run at full power, AND it's like a leaf blower compared to the G1 Insight fan. You'll need at least a 10A/12V power supply.

Recommend you NOT discharge the pack. Grid charge for 25 hours and reinstall. Assess behavior.

The battery can accept flow into either end. It doesn't matter which you choose. Just make sure you can feel a trickle of air moving through it at the outlet.

Worth noting that the HCH2 battery is completely different from the G1 battery in every meaningful way. They have the notorious distinction of being one of the worst hybrid batteries ever made. Good luck.

 

Thank you for the reply. You helped me tremendously with my G1 Insight in the past and I really appreciate your help.

Yes, I probably made a mistake by buying the car. I was willing to take a chance on it for the $1900 that I paid. On the plus side, the HCH2 is much safer and in my opinion, far more comfortable than the G1 Insight.

I did actually already perform one 20 hour balance charge but that was more of a test to see if my grid charger v2.0 was working properly. The balance charge was ended at 20 hours because I wasn't sure if the fan I used for cooling the battery outside of the car was providing enough air flow. I can perform another balance charge for 25 hours per your recommendation. Is there a risk of further degrading the HCH2 battery with discharging? .

Thanks again.

 

At 350mA, if you can feel air flowing through the battery, it's sufficient. If that exit air is > 110°F, terminate charge early. Allow cells to cool and charge again for the earlier of 8 hours or until temp hits 110°F again.

The HCH2 battery has 132 hot spots in it (one per cell), so it's subject to premature failure. Discharges can take a battery that limps along to one that won't work at all. If you find that a 25 hour charge doesn't give you recalibration-free option, the battery is in bad shape. Then the choice becomes, 1) risk discharge to 99V immediately after a 25 hr charge knowing it may kill the battery, 2) limp along as-is with regular charges, 3) replace battery.

 

I understand. Even with my lack of technical knowledge I can see how poorly the air flows around the staggered sticks in the battery.

How often do you recommend I perform a 25 hour balance charge? If I remember correctly, with my Insight, you suggested an 8 hour charge once per month to help with the self discharge of the cells. That routine served me well with that particular battery. I have a feeling that I won't be so lucky with the HCH2. Luckily most of my driving is highway and I'm very conservative with my use of the IMA.

Thank you very much for your help.

 

Another thing that I wanted to mention is that I have some previous service records and it looks like the car had the most recent software installed. It also looks like there has been at least one battery replacement due to the three character code on the battery label. I think the code was CA2 but I'm not sure. There's some info in the service manual about this but I didn't see that particular battery code mentioned. It could be a junkyard battery for all I know. There isn't any label in the door jamb from a dealer installed replacement battery but the sticks are definitely orange and green.

 

IIRC, all HCH2 sticks are orange and green. CA2 have red plastic end caps visible on the end opposite the junction board. Others are white/translucent.

Frequency depends on condition. Recalibrations can be used as a signal for a grid charge.

 

Thank you once again for sharing your wisdom. I do have a few more questions if you don't mind.

1. For grid charging in cold winter temperatures, would the IPU fan running at full speed be too cold (temperature of 30 degrees or less) for a successful grid charge? If so, I'm assuming that I would need a PWM controller to allow the fan to run at reduced speed.

2. It looks like the IPU fan has four wires (GND, PWM, TACH and 12V+) . In order to make the fan run at full speed, do I connect the GND to the PWM? Do you have a recommendation for what to use to make the connections? I was thinking about getting an additional harness to go between the car harness and fan harness and make my splices there. Not sure if the connector genders will work.

3. If I continue to perform balance charges only will the pack lose capacity over time due to voltage depression?

4. Is there a way to assess whether a battery is a good candidate for discharging or is it just a guess?

Thank you.

 

1. yes.

2. GND and PWM to (-), 12V+ to (+)

3. Possibly.

4. Guess.

 

Thanks again for your works of wisdom. Very much appreciated.

Just finished the 25 hour balance charge. Final voltage was 193.

I have two things to share with those who might be reading this thread. First, it might be a good idea to leave the fan running for a period of time after ending the charge to allow for the battery to cool. Second, if you're using an inexpensive $6.99 7-function digital multimeter from Harbor Freight (also available from other sources) and getting strange readings you might want to replace the 9 volt battery. In my case the grid charger voltage seemed to be fluctuating in a strange way that I hadn't experienced before. After replacing the 9 volt battery in the meter (old battery was only at about 8 volts) everything was normal. Just to be certain, I switched to my Fluke multimeter for confirmation.