Hi From Central Missouri - NIMH Powerwall Build

Hello Powerwall builders!

I have just started my journey on building a 1600 cell NIMH Powerwall.

I will be using recycled Panasonic HHR-450 Cells, 1.2 volt at 4.2 amp/hr.

Built my first test pack of 10S4P and doing testing now. Will soon have load tests with wonderful charts, and graphs and 8x10 color glossies. So far, the test pack has exceeded my expectations

I have 1 KW of PV that will be charging the system.

Phase one goal is 10s80P at 12 volts 320 amp/hrs

Phase 2 goal is additional 10s80P for a 24 volt system

Hope to have youtube vids and a dedicated web site Titled NIMH Powerwall.

Lets have lots of fun as we follow my journey into the unknown.

JimU

How come you went with NiMH?

I can't tell in the last image of the finished pack, but if you haven't done it yet, I'd suggest using a zip-tie to hold the bus bar on the ends in place. Glue and fuses won't be good enough in the end as the glue can let go from lateral stresses and the fuses can break as well. The zip-ties will help keep it in place.

What kind of projects do you plan on running off this setup?

Korishan said:

How come you went with NiMH?

I can't tell in the last image of the finished pack, but if you haven't done it yet, I'd suggest using a zip-tie to hold the bus bar on the ends in place. Glue and fuses won't be good enough in the end as the glue can let go from lateral stresses and the fuses can break as well. The zip-ties will help keep it in place.

What kind of projects do you plan on running off this setup?

Click to expand...

Hi Korishan,

The main reason I have gone with NIMH is that I have 1600 free cells from lightly used medical packs and have access to an unlimited supply. Plus, I thought it would be a fun challenge to see what roadblocks lie ahead in using these cells as a powerwall.

As to the construction of the test battery pack, I totally agree on the construction. I will be using standard build practices on the 10 80P packs.

When I ordered my cell holders from an ebay seller, I got a bait and switch.. These holders do not have the 4 small tabs to hold the cells in place, so in order to build the test pack of 10s4P i just cobbled it together with some hot glue.

I will be ordering from another seller to get the correct cell holders so my bus bars can be zipped tied properly.

As to what use I have for the powerwall, is that I have an aging Lead acid PV storage system, and it will soon need to be replaced. Presently it provides backup power to the JimU household.

Regards,

Jim

Ahhh, ok. It all makes sense now