I have built a grid charger and have charged my IMA pack off the car. I have also installed a harness to charge the pack in the vehicle.

Due to my present circumstances however, I am not able to connect to the grid. So I started wondering if it may be possible to charge using a portable 40 watt solar panel connected to a 12 volt lead acid/ lithium ion pack, which would connect to an inverter that I already have.

My question: Could I connect my grid charger to the inverter 110V AC outlet directly, knowing that the inverter does not output a perfect sine wave? Could the meanwells handle that?

 

Maybe. I can't say how tolerant the meanwells are of non-pure sine wave AC power. I would expect their flexibility in input would make them fairly tolerant.

Not sure what you mean by the above bolded/italics part.

At peak voltage, assuming 350mA current, you'll be pulling about 70W before inefficiencies. Maybe 100W after PS and inverter inefficiencies.

Of course, we're not even talking about driving the fan. I assume you have constructed a PWM fan controller to drive the stock fan. If you haven't, DO NOT EVEN ATTEMPT GRID CHARGING AS YOU ARE LIKELY TO COOK YOUR PACK.

Also, because it's happened before, NEVER ATTEMPT CHARGING WITH THE IPU COVER OFF. WITH THE IPU COVER OFF, THE COOLING SYSTEM IS RENDERED NON-FUNCTIONAL BECAUSE IT RELIES ON THE SEALED COVER TO SUCK AIR THROUGH THE BATTERY FROM THE REAR DECK AND EXHAUST IT INTO THE TRUNK.

Assuming you have an 8-10A 12V supply to drive the fan... yeah... it's a beast. You're looking at another 100W if you go 100% duty cycle or 50W if you're running 50% duty cycle (50% is probably fine).

Now you're power consumption is 150-200W. A HEALTHY ~40Ah 12V battery will only run that for about 16 hours. you need to grid charge for 24. I wouldn't bother with a lithium ion pack (assuming a jump pack). All their Ah ratings are outright lies. The 40W solar will likely only offset 30W for 5-6 hours average unless you have it on a tracking mount.

 

Thank you very much for your input, Steve.

The bolded italics you referred to: I just meant that I had taken the IMA pack out of the car and charged it inside my house; with a fan cooling it all the time of course. I've done that a couple of times already and finally decided to install a harness to charge in the car. Removing and re-installing that pack is quite a pain. I had bought a spare used pack last summer, so I keep one ready to go at all times.

My aim with this solar charging was not to charge once in a blue moon but perhaps every day for a few hours. So I could be topping off the pack regularly, hoping to thus avoid long charges of 24 hours. What are your thoughts on that?
To answer your concerns over cooling, I understand about the IMA cover and would never charge with that off - that's the reason I installed the harness with charging port in the trunk.

I do have the PWM fan controller that you had linked to in one of your other posts so yes, I would definitely keep the fan running during charging.
I see though, from your numbers, that I would need a much bigger PV setup than I already have, to do this. However, I do not have the time or finances at present to undertake that, so maybe some time in the future.

Thank you once again and if I get this going I will be sure to update you on my results.

 

If you've charged it a couple of times outside the car, you've likely balanced it as much as possible. I'd recommend ONE MORE 24 hour charge out of car and then a discharge to 132V with 2X 100W incandescent bulbs in series followed by a discharge to 106V with 2X 60W lightbulbs in series followed by another 24 hour charge.

Every time you grid charge, you risk the possibility of capacity loss due to overcharging. A discharge to 0.8V/cell average will reclaim a lot of lost capacity.

I wouldn't rule your scenario out entirely. You could tie the "charging" 12V into the 12V system and replenish it with the car as well. It would probably work if you could drive the IMA charger for 12+ hours at a time. It's not as optimal as a solar setup as you'll be burning a little extra gas, but if the goal is to maintain the battery, it would probably be a net benefit.

I've often wondered if using your setup DURING driving and powered by the car's setup would be beneficial. I think it might on a long trip as the net effect would likely be a constant slow current into the battery even if the DC-DC is pulling more total energy I don't know the algorithms, but I suspect the surplus electrons needed to charge the 12V driving the charger would likely come more from gas/IMA motor than it would the HV battery itself, particularly if you're running a 5-6 hour drive.

I've even looked at DC-DC converters that step 12V UP to voltages that could charge the IMA battery... I just don't have an HCH2 anymore...

 

Sorry I wasn't clearer. When I said I charged it a couple of times, I meant the entire procedure following your recommendations: Charged to 190V, discharged using 2 X 60W to 158V, then 2 X 40W to 106V. Then Charged back up to 190V. Entire cycle has been done twice on my original pack and once on the spare pack.

Actually, the spare pack went all the way up to 195 V and was still climbing further, rising by a tenth of a volt / hour and flowing a current of 348mA. However, fearing overcharging, I stopped the charge cycle at that point which was just 9.5 hrs after starting. This pack then sat in my basement for about a month and a half, after which I found the voltage had dropped to 174.5V. I gave it one final topping off charge which lasted just 3.5 hrs, at which point the voltage had reached 193.2V. Again fearing overcharge, I stopped there and reinstalled the pack in my car a day later. I was a little disappointed to notice that the pack did not perform as well as when I had bought it used last summer (it had run well for about 6 months before it began to recal frequently.)

My original pack had been sitting in my basement for 6 months while the spare was installed. First week of April, I charged-discharged-charged the original and switched packs on the car. The original worked really well for about a month and then started declining, so end May I charged-discharged-charged the spare as mentioned above and switched packs again. I'm running with the spare now but as I said it's already showing some weakness - a few quick recals although no IMA light yet.

I wonder if I did overcharge my spare pack when it went up to 195V?

 

Note that all of my advice/comments assumes that you have all-original packs, and not aftermarket Chinese cells in your pack. The Chinese stuff is different than the original Panasonic, and all I know is that they behave differently. I have attempted to recondition ONE Chinese Insight pack, and it was a complete failure.

"Charge to 190V" isn't a termination criteria unless, 1) it's been 24 hours, 2) voltage hasn't risen for 4+ hours, 3) You've noted a 2V+ drop, or 4) the temperature of the air exiting the pack is 30+ above the inlet or >100°F

At 350mA w/adequate cooling, It's almost impossible to damage the pack from "overcharging". If you could feel air flowing through the pack at the exit, and it was not over 100°F, there's almost no way you damaged it.

You should be getting good at swapping packs at this point. Round trip for me is about 20 minutes.

You likely need to break both packs down and try to build a good one. Here's how I would do it with little to no testing ability:

Start with the uninstalled pack:
Note how long it has been sitting
record all 11 voltage tap readings
24 hour charge
Discharge to 158V
record all 11 voltage tap readings
Discharge to 145.2V.
wait 10+ hours
record all 11 voltage tap readings
Wait 21 days
record all 11 voltage tap readings
Grid charge for 24 hours
Install in car

Repeat for other pack

Assess the results, conduct some additional voltage measurements on the candidate subpacks and build a pack.

 

Sorry. Got caught up in other business.
Well its a relief to know I probably haven't damaged the pack.
Not sure when I'll get some time to do all those things, but I will. And when I do, I'll get back to you with the results.
Thanks for all the info, Steve. I have a question about the tap voltages. I noticed the image you sent me has 2 sets of numbers. When I test B14 to B6 or whatever, do I go by the VHB numbers above the wire colors or just the pin numbers? I'm thinking the pin numbers and just ignore the VHB numbers.

 

Yep. Pin numbers. Ignore VHBX

 

Sorry it took me so long, but I managed to check both packs and here are the results.

For my spare pack, which had been fully charged before it sat in my basement for a couple months, these were the voltage measurements:

15.48, 15.41, 14.25, 15.63, 15.61, 15.61, 15.62, 15.62, 15.62, 15.63, 15.63

Did 24 hour charge.

After discharge to 158 volts:

14.35, 14.31, 12.18, 14.74, 14.73, 14.72, 14.76, 14.75, 14.73, 14.76, 14.75

After discharge to 145.2 volts and waiting 10+ hours:

13.85, 13.71, 14.37, 14.84, 14.84, 14.79, 14.86, 14.83, 14.8, 14.84, 14.82

After waiting 21 days:

11.99, 10.21, 13.62, 15.09, 15.09, 15.05, 15.11, 15.08, 15.07, 15.09, 15.08

You can see that the first 3 sticks dropped significantly lower than the others.

For my old (original) pack:

After sitting for 17 days:

14.66, 15.03, 15.65, 14.9, 14.76, 14.56, 15.7, 15.31, 14.91, 15.43, 15.22

Did 24 hour charge.

After discharge to 158 volts:

13.79, 14.15, 14.37, 14.24, 14.1, 14.06, 14.46, 14.35, 14.27, 14.38, 14.44

After discharge to 145.2 volts and waiting 10+ hours:

14.44, 14.32, 14.68, 14.46, 14.25, 14.35, 14.76, 14.58, 14.46, 14.6, 14.69

After waiting 21 days:

13.64, 13.41, 14.68, 13.91, 13.43, 13.39, 14.84, 14.2, 13.75, 14.12, 14.19

This pack is behaving better than the spare, which recals immediately after installing in car. This (my original pack) is the one I am currently using. It's doing well as long as I charge it (in car) every week or so.

As I cannot currently keep the car off the road for enough time to disassemble the packs and exchange sticks, that step is on hold for now.

If I open up a pack, how would I know which sticks correspond to which "B" numbers?

 

A google sheet would have gone a parsec closer to ease of use.

I'm not willing to try and sort through that mess. Going strictly off the first data set for the spare pack, the first 3 subpacks are clearly bad. The remaining 8 above 15.60V are likely good. The first two are probably work-able for brief periods, but the 3rd is shot.

EDIT: to answer your question, you could trace the wires from the orange connector to the end plate. Or you can just re-measure the subpacks. I used to know, but that information fell out of my brain a long time ago.

After trying to muddle through it a bit, the 8 nearly identical voltage subpacks from the spare pack are likely excellent - far superior to anything I see in your pack. I would attempt to build a pack from the following:

S: 1, 4-11
O: 3, 6

Since timing is an issue:

Identify the 3 weak-ish subpacks in "S" and conduct 24 hr charge, disassemble and let it sit for 24 hours
Conduct 3X 12V resets and idle charges in-car before you remove your O pack. This will ensure the two decent subpacks will be charged to near 80% SoC.
Pull "O" pack and build S+O pack using the subpacks above.
Grid charge on bench overnight.
Install in the morning.

Car will only be down one evening and night.