Hybrid battery charge weird fluctuation

todd's a straight shooter and a member here. since you purchased the car from him, might as well start there and see where it goes. if you are looking for a low cost long term solution, unfortunately, we're not there yet.

if you just need to get by for the warranty period of a rebuilt, you still have to deal with potential warranty hassles.

imo, a 2008 is a rock solid car that deserves a new battery.

 

Hello,
I am the CEO of NuVant Systems. We developed the technology used by Green Bean Battery, Hybrid Battery 911 and about 30 other companies world-wide. We designed the equipment at the request of Automotive Diagnostic Services in Chandler Arizona four years ago. This is in part why you have all these new shops that appear to have popped up from nowhere. The reconditioning protocols we use are decades old. The technique is a variation of a CCCC (constant current-constant current) method that you can read about in the Linden's Handbook of Batteries, 4th edition. We are now developing reconditioning processes for lithium ion batteries. Those methods will be based on the CCCV method, which is constant current-constant voltage methodology. More recently I authored “Electrochemical Energy Storage: Current and Emerging Technologies” chapter in the Handbook of Industrial Chemistry and Biotechnology. I discuss CCCC and CCCV in that chapter.

Memory effects are likely to occur whenever batteries are subjected to repetitive shallow depths of discharge. This is certainly the case with nickel metal hydride batteries in the Prius. Actually, the precursor to the nickel metal hydride battery is the NiCad battery. The cadmium was simply replaced with metal hydride. The general structure of the battery, including the starved separator remained the same. NiCad batteries have a memory effect. The fact that the memory effect was retained in the NiMH batteries suggest that the issue is with the nickel oxyhydroxide (positive electrode). While the memory effect is still not fully understood, the methodology to mitigate the problem has been well understood for decades.

If anyone is interested in learning more, I would be happy to hold an on-line class on the topic at no charge.

Best regards,
Eugene S. Smotkin, CEO
NuVant Systems Inc.
&
Professor of Chemistry
Department of Chemistry and Chemical Biology
Northeastern University
Boston, MA 02115

 

This is interesting; I am guessing this is better done sooner rather than later due to entropy given our batteries are getting quite worn now; I am not an expert by any means, and have no qualifications in chemistry or electronics or mechanics or computing,but do like the sound of constant current charging for lithium reconditioning; I have an old variable current charger for my EV, but is slows down once it gets to 80%, which is annoying. I would rather charge at a constant current right up to 100% without the slowdown. I like to keep my EV charged fully whenever not in use to prevent discharge below 60%, to keep the battery healthy for longer. I do the same on my Prius, I try to avoid draining the battery down, and often drive down long hills so the battery can be fully charged before I park it up for a few hours to let the voltage settle as I think that keeps the battery alive longer? I still have the original 12v battery which is now 12 years old so that might be a good sign?

Would be grateful for your advice on how to keep my cars going for longer!

Cheers,

Richie Koppf