I would guess the HCH battery packs might be a little cheaper because there are more of these cars on the road (greater volume usually makes things cheaper), and since the car is physically *bigger*, it's probably easier to work on and thus the labor cost is probably a little less than with the HIH. Either that, of maybe batteries are just cheaper in Maryland? Who knows?

I paid the technician a nominal fee ($35) to test the IMA. I suppose you could do it yourself if you had the testing equipment and knew what you're looking at. But I'm so hopeless with mechanical things that I'm lucky if I can operate an electric screwdriver correctly.

 

This may be more information than you ask for but here is a link to an article on battery life cycles.

http://www.epriweb.com/public/000000000001009299.pdf#search='nimh%20battery%20re placement%20criteria'

On the subject of capacity testing I can say don't try this at home but here is how it might go. You must start with a fully charged battery. The batteries capacity is 6 amps per hour. That is to say if you put a constant 6 Amp load on the battery it would reach its discharged voltage of .8 v per cell (96v) in one hour. To do this you would need a constant kilowatt loadbank. If it took 45 minutes to reach the discharged voltage (96v) the battery would have a capacity of 75%. I do know that for lead acid batteries capacity does go down exponentially. For valve regulated - flooded cell lead acid batteries it is recommended that you replace them at 70% capacity as they tend to degrade very rapidily after that. I do not know what the replacement criteria is for NiMh batteries is or how there capacity degrades over time.

I used the 144v battery in the HCH for the example above.

Hope this helps.

Jeff

 

noto check your private mail box please.

 

Chances are that the battery won't be the first thing to break on the car... for that matter, your typical non hybrid car will have a major mechanical failure before the battery of your hybrid needs replacement.

 

Yes, the battery pack is rated at 6Ah, but that is not the range of use that the IMA ECU is programed for. If you run the battery down to its nominal empty and then charge it up to nominal full, then you run into the nominal stated cycle life problem, i.e. 500 to 1000 full cycle charge/discharge life.

Honda runs the battery pack from about 40% charge to 80% charge give or take 10%, doing that you nerver have anode/cathode breakdown, nor do you vent moisture out of the battery when it is over charged at the full point. One of the previous posters was correct, you end up with 5% of capacity change in about 100,000 miles, and it is linear. At least that is what we do on nuclear submarines...

Mark A. Delagasse, USN, Ret.