Replacing NI-MH batteries to Li-ion?
 

i wondered if anybody tried it in real life.
D cell Ni-HM batteries are 1.2v 6000mAh x120.
How about 26650 3.7v 6000mAh x40 batteries?

Not sure if these small ones strong enough for the current.
My idea is to swap 6 Ni-NM batteries to 2 Li-Ion. Cost would be huge difference. It would be £300 instead of £2000 aftermarket or £3000 for a Honda dealer.
Any experience ?

Re: Replacing NI-MH batteries to Li-ion?
 

The short answer is no. Because anyone with a basic knowledge would know it's not possible. You haven't done any research of any kind beyond trying to match voltages. The explosive battery fire the first time regenerative braking is used would be spectacular.

A 6 cell NiMH stick ROUTINELY sees 9-10V. Anything above 8.4V for LiPo 2S is an explosion.

What you propose is not possible without detailed knowledge of how the HCH1 MCM/BCM handles data. You need to spoof the computer with the data it needs, and you need to be able to control regen and assist according to a new set of rules that you develop according to the cells you choose.

Typical charge limitations on cheap cells of that type are in the 2-3A range. That means you need 25 cells to replace 3 NiMH cells or 50 26650 cells to replace 6 NiMH cells... yes. That's right. You need 1,000 cells.

Why do you think Tesla has something like 7700 18650 cells in their Model S pack?

Take these high drain LiFePO4 cells:

https://www.batteryspace.com/prod-specs/6610.pdf

You'd need 3 in series to replace 6 NiMH, and you'd need 5 at each level, so that's 15 cells to replace 6 NiMH. At 300 cells per pack, they're about $12 EA in those quantities, so you're at $3600 for the cells alone not to mention all the custom fabrication and hundreds of man hours of work to get it done.

If you want to see the work being done on the Insight and somewhat on the HCH1, head over to insightcentral.net. What is certain is that ALL lithium solutions cost substantially more than a NiMH pack.