299 total cells. These made it through the first charge and storage. Im not sure how many dead cells came out of this lot. I think I had less than 5 that self discharged. I'm glad I got rid of those, but the rest of them kept their voltage fairly well over 3-4 months of storage.
39% good cells...
I got a lot of "refurbished" HP 9 cell 93 WH batteries that have a a nominal voltage of 11.1 and a capacity of 8100 mah.
They are new packs with maybe some shelf time, but they look great. The cells and the...
All I have to say about poweroak is WOW!
It's a powerwall appliance.
They also make smaller...
I have all of the components now to charge batteries using tp4056 circuits I purchased from ebay. The only problem is they have no reverse voltage protection as stated in the description.
With theopus, I can accidentally put a battery in backwards without harm.
For those who use the tp4056...
I want to ask a question to the Group on DIY power walls, is anyone planning for cooling?
I think that keeping the temperature of the cells below 40C would be pretty important.
I just watched this video from 2013 by Jeff Dahn.
The several takeaways that I got from the video were the...
I am an engineer from Central Illinois, USA whojuststarted collecting batteries to build a power wall. I have been inspired by the youtube videos from
Jehu Garcia, HBpowerwall, Mikes diy powerwall etc.
Main goal in wanting to build a power wall is to learn. I hope to change jobs in...