So it is looking like my IMA battery has completely kicked the bucket. Some info on my car and situation:

2008 Honda Civic Hybrid, 118,000kms

Was totally fine until 2018. Car was left in storage for 15 months while I was overseas. No one to drive it or keep the battery healthy. It maybe have been driven once during this time. Replaced 12V battery on return. Pretty sure this incident complete destroyed my IMA (I had no clue I should have had someone drive the car every month, and neither did anyone in my family).

A few months after returning back, I started getting recalibrations. They got worse and worse. Recently I had an incident where the 12V battery light came on as IMA had drained so much it was not charging 12V through DC-DC converter. Disconnecting 12V solved that issue. Then IMA light started coming on. I noticed the battery was not holding a charge overnight.

I figured it was worth trying a grid charger and ordered a Maxx Volt EL-1 Grid charger (no discharger), got it all hooked up and let it charge soak for 24hours. Keeping a voltage record and checking temps every hour I was awake. Car seemed fine for about 1-2 days and then batteries complete drain and IMA light comes on again.

Unfortunately, since I live in Canada, my battery replacement options are far more restrictive than in the USA. (I could use a USA reseller like Bumblebee but the overall cost would be IMMENSE). There is ONE battery dealer near me, GreenTouch Hybrid. They said they would replace my pack with another pack that has new sticks in it. Cost could be about $1600 CAD all in. 2 year warranty, unlimited KM.

However they said a few tings that raised red flags with me. I asked if the placement pack would be the 2006-2008 pack of the 2009-2011 pack as they are different, and the 2009-2011 pack is far worse. They told me that the only difference is in the cooling solution in the car, and that since only the battery is getting replaced, it does not matter. I am fairly certain that from research here that this is completely untrue.

Is there anything I can do to revive the pack? Would a grid discharging help or is the pack already toast due to rapid self-discharge? (Help S Keith)
How long could I expect a "new cell" pack to last?

Thanks and Regards.

 

Sorry to hear it.

EL-1 output is typically lower than HA offerings. You need to divide 8800 by the output current of the charger and charge for that many hours, e.g., if the output is 260mA, then you need to charge for 34 hours.

It's unlikely that you fully charged the battery during your last exercise. Fully charging and over-charging a hybrid battery is a critical operation for possible restoration.

How were you checking temps during the last charge?

If you purchase a "new cell" pack, you are likely getting Chinese cells - much like what all battery builders use, but at that price point, you're likely getting the cast offs of the inferior supplier; however, your question is somewhat relevant, and their response is telling. The meaningful difference between 06-08 and 09-11 is the spacers. The stick pairs are actually spaced the same; however, the spacers are fatter on the outside meaning each dual stick subpack has more gap with its neighbor in an 09-11 vs. 06-08. It's the uneven gaps between sticks in 09-11 that caused massive hot spots and premature failure.

It depends on if they're sourcing individual sticks and gapping them, or if they're buying stick pair subpacks. They'll probably never tell you.

I recommend you extend the grid charge to the calculated time and ensure the cooling system is working properly by verifying airflow at the exit duct located behind the right rear panel in the trunk and at the inlet on the rear deck. IPU lid MUST be closed and sealed with all bolts installed.

If that doesn't fix your issue, it might be a useful tool to assess the health of the 11 subpacks and source/replace only those you need.

 

Thank you so much for your input S Keith. Here is some more info on the charging I did. I force recharged the battery with the car before grid charging, here are the currents and voltages over time:

24 Hour Grid Charge

Unfortunately it seems I got my airflow path backwards, as I was feeling the intake air thinking it was exhaust. The exhaust is on the right side behind the trunk liner? I will say the temperature in the trunk never felt warmer than ambient, and the intake was sucking in lots of air. I always made sure the windows were down and the trunk was partly open during charging, so hopefully nothing overheated.

I was very careful to make sure all covers and seals were back on tight, and lined up properly.

Something strange to note. It seems like the car THINKS it drains complete overnight when it does not. This morning when I put my key in the ignition and attempted to start it, the battery Negative Recalibrated from full to 2 bars and needed to use the starter to turn on. HOWEVER I plugged the grid charger in to check voltage and it reported the "2 bar" voltage at 174V. Isn't this in the higher operating range?

When I visited that battery shop, they actually opened a box and showed me the batteries they get for installation. They seemed like double sticks. It honestly is a little hard to remember because it was months ago.

Since this grid charger charges at around 290ma, would you recommend a 30 hour charge? Do you think getting MaxxVolts to sell me a discharger might see some benefits? I originally wanted to purchase a charger from Hybrid Automotive, but due to the USD/CAD dollar difference, imports, and shipping costs, the HA charger cost double.

Regards.

 

Didn't see that you force charged before. I assume you did that via multiple 12V disconnects and starts until the battery showed full?

As long as you can detect airflow, cooling should be sufficient. The purpose of leaving the trunk open is more to prevent the charger itself from overheating. The cooling system works by inhaling air conditioned interior air and dumping warm air in the trunk. The trunk is vented to prevent back pressure from accumulating; however, operating A/C on max all the time can cause a slight vacuum in the cabin and inhibit airflow/cooling. However, in your region, this is rarely a concern.

The voltage drop you witnessed at the end of the grid charge is indicative of a mostly filled battery, so subsequent charging may not yield any fruit. Excessive self-discharge is usually not correctable with discharging.

Operating range of the battery is approximately 132-211V. The 158V nominal voltage is never actually seen at rest UNLESS the battery is completely empty. The nominal voltage is used for the purposes of calculations and doesn't have a lot of meaning outside "ratings." People often don't understand that battery voltages fluctuate wildly. A 12V battery is often charged at 14.4V and isn't empty until 10.5V. Batteries also respond to current. If you discharge current, the voltage of the battery drops in accordance with V= I * R where I is current in amps and R is resistance in ohms. A very healthy battery pack will have a total internal resistance of about 0.2V. A 100A discharge current under max IMA demand would instantaneously drop the voltage 20V. Resting voltages also have very little meaning, and what little meaning they have isn't obtained until the battery has sat undisturbed for 10+ hours. Your measurement after start was measuring the resistance of "excited" cell chemistry and could be 10V or more lower in just a couple hours.

Total pack voltages are completely useless in diagnostics. A single failed cell may cause only a 0.3V variation in pack voltage - essentially undetectable.

I recommend you drive the car normally until Friday. Let it sit overnight, 10+ hours. Pull the IPU lid and measure the 11 tap voltages to XX.XX accuracy. You are directly measuring the 11 stick pairs when you do this. If you find that you have 10 nearly identical readings and one outlier, you may find that you only have a single bad stick pair and can likely source one and replace it yourself.

If you have alternate means of transportation, it would be better to let it sit for another 7 days after the initial readings and then repeat the voltage measurements. The additional 7 days will improve the diagnostic value of the readings and possibly indicate that additional subpacks are questionable and should be replaced to increase the duration of the repair.

I've never personally handled any of the Chinese stick pairs. If they had spacers already on them, then they should have different sets of spacers for 06-08 and 09-11. If the sticks do not have spacers, then the shop may have to modify stock spacers to make them fit. If you INSIST on a 06-08 case as a replacement, that should address all concerns as 09-11 sticks won't fit in a 06-08 case without swapping spacers.

 

Thanks Steve.

I did the triple 12V disconnect and calibrate method after my 24Hr grid charge.

Do you have any diagrams or links showing the 11 voltage tap locations?I can let the car sit over the weekend and check the tap voltages and report back. If I can get by with just replacing a few stick myself that would be ideal.
Unfortunately the car is the only method of transport for the household.

Regards

EDIT: NVM, Think I found the voltage point measurements it in another forum post. Here: https://www.dropbox.com/s/l4sj188ldw...Check.png?dl=0

 

https://www.greenhybrid.com/forums/f...rminals-31418/ link in 2nd post. You simply probe the back of the connector while it's plugged into the BCM.

 

Steve, if I just switched off the IMA master breaker, and drove the car around with the IMA bypassed, would that also be equivalent to "letting the car sit" ? That way I can still use it to get around and be able to perform my testing.

Driving in Second gear would probably help keep the RPM in range.

 

The master switch completely isolates the battery. If you can confirm 12V charging in the 1600-3500 rpm range, that might do it. I just don't remember if 12V charging will still occur with master off. It won't on the prior model without disconnecting one of the BCM harness plugs.

Your proposal will work if you get 12V charging. Good thinking.

 

Keith, Can you tell me which ODB2 Protocols our car uses? I attempted to use a bluetooth OBD2 reader which scans:
- OBD2 ISO CANBUS
- OBD2 SAE J1850 VPW/PWM
- OBD2 ISO 14230-4 KFP Fast and Address
- OBD2 ISO 1941-2 ISO address

It reports that my car does not use any of these protocols, so I need to return the scanner. I have to find something that supports this car.

 

I have no idea, but I've never encountered a code reader that can't read the basic DTC data. I suspect the issue is a bad code reader. I recently purchased one that sounded great... unfortunately, even though it would report some limited real-time run data, it wouldn't read codes that other cheaper OBDII readers could pick up.

EDIT: you can also "blink" the codes:

http://99mpg.com/categories/insight/readingtheblinkcod/

The codes on that site don't apply, but the process of shorting the pins and counting the CEL and IMA light flashes is the same. I can check the codes for you in the manual. Technically, this is more robust that plain OBDII code readers as some codes have different sub codes. The numbers derived from the blinks are actually the sub codes.