Saw this over in the HCH-2 forum. The US DOE has a fleet of electric/hev/etc vehicles that they keep maintenance records and whatnot on. They've got 4 HCH-1's on there, 2 driven for around 30K and 2 driven around 150K.

Here's the interesting part. Both of the long-termers were driven for about 150k. Both had their catalytic converter die around 100k. Both had a CVT failure (equalling replacement) around 100k. Ouch. Makes me glad I have the MT. But no battery failure reported! It's a pretty small sample size, I know. But interesting that both had the same failures at the same time.

You can find all the data here: http://avt.inl.gov/hev.shtml

But the interesting ones are the 2 long-term HCH-1's:
http://avt.inl.gov/pdf/hev/honda_civ..._sheet3864.pdf

http://avt.inl.gov/pdf/hev/fact_sheet1603.pdf

 

Operating 24 hrs a day, six days a week. No battery failures. Conclusion...don't let the tires get cold and you are less likely to have battery problem.