I'm still getting mid to high 50's but for 137,000 miles, the acceleration power is really dropping off. Can anyone direct me to where I can buy the batteries separate and maybe a good price. If I were to replace the entire hybrid pack, it would be about $3000. Ouch!
Thanks in advancwe guys and gals!
IMA battery pack degradation will cause a more fragile SoC. The State of Charge indicator opposite the fuel gauge will more frequently fall to a low level and require frequent forced charging.
http://www.insightcentral.net/forum/vie ... fdd3075a64
You will only notice a loss of power if the IMA SoC isn't robust enough and a "normal" driving style rapidly depletes it. You will only notice a loss of MPG if this frequent depletion requires a _frequent_ forced charge (especially highway miles, city miles will fall somewhat less)
The problem in a DIY replacement of the _batteries_ in the pack is *matching* each cell. No matter how you approach it the pack will be "live" with 144v as you disassemble it. And the thermal sensors that attach to each cell group must be transferred to the new cells.
AFAIK there have been no posts _anywhere_ that outline this procedure, which may be simple or complex.
If you don't assure that each of the 120 cells are reasonably matched in their capacity the weakest cell in the array will pull down the others. Depending on the specific differences it may only take a few weeks!
Radio control car racers used to have a trick tester to evaluate the performance of the NiCad batteries they used. This would "grade" the batteries capacity which could make the difference between a win and loss. Unless Panasonic is _extremely_ quality controlled in their manufacture of our NiMH batteries something similar would be needed for matching the cells in the Insight. Which _may_ require sorting many more cells than 120 to get a good match.
But if your up to the task:
http://www.panasonic.com/industrial/bat ... index.html
I've lost the old link that specified the screw lug type D cell.
Hope someone else will post it. The cost of 120 cells was in the 800-1000$ range.
But the narrative does specify prismatic cells and AFAIK Toyota is the only one using such cells in the Prius. Panasonic is the OEM manufacturer for the Insight cells.
edit: FOUND IT!