View Single Post
Old 09-21-2021, 06:37 PM   #26 (permalink)
Isaac Zachary
High Altitude Hybrid
 
Join Date: Dec 2020
Location: Gunnison, CO
Posts: 2,080

Avalon - '13 Toyota Avalon HV
90 day: 40.45 mpg (US)

Prius - '06 Toyota Prius
Thanks: 1,129
Thanked 584 Times in 463 Posts
Quote:
Originally Posted by redpoint5 View Post
I've not been impressed with the longevity of any NiMh things I've owned. In theory they need less management... the Roomba and Neato vacuum robots that had NiMh batteries would kill the battery in about a year regardless of how often you ran it. The lithium ion replacements people made have gone years and still haven't died yet.

That said, it seems replacing NiMH batteries might be more straightforward for a DIYer like me.

I think I read somewhere that someone was replacing weak NiMH batteries in Prii with LiFePO4, but I could be mistaken. Lithium ion batteries don't like to be charged below freezing as you pointed out.

I expect to either have access to junkyard batteries when it comes time to replace, or be able to affordably DIY a replacement.
It seems that there are a few trying the LiFePO4's as a direct replacement in their NiMH hybrids and are having successes, so far at least.

The freezing aspect makes me a bit weary too.

The good news is that the charging characteristics that keep the NiMH batteries within 25 to 75% make the LiFePO4's go closer to 10 to 90% giving you more capacity that way too.
__________________
  Reply With Quote