Battery Balancer

Hi I was wondering if anyone on this forum has or knows someone who might have a battery balancer similar to a Hitec 4x they might be willing to let someone borrow or rent for a few days. They are often used in the RC hobby world. I am going to cycle and balance the cells in my Prius and have more balancers will speed up the process.

Eric ✉
Oct '14

You only hook it up to individual cells in the battery and there are 28 cells in the HV battery pack. The balancer I bought will do 4 cells at once. and it takes about 1 day for 4 cells so it's about a week of cycling I am looking at. Have a second balancer that does 4 would cut my time in half. But they cost about $130 for the balancer and since I won't have any other real use for it I only wanted to buy 1.

Eric ✉
Oct '14

Yeah I did also until I started looking into this process. In the spring my Prius popped an error code stating there was a problem with the HV battery. I found I had 3 options. 1. Go to Toyota and have the battery replaced. Possibly at a cost of about $3500 or more. The car has about 170K on it. So that option was out. 2. Find a junkyard or rebuilt battery at around $900 and swap packs and hope the replacement is good. 3. Take the battery pack out myself read the voltage on each cell and find bad cells and replace them. I took option number 3. Everything was fine for the last 5 months. Now there is an issue with another cell possibly. I started reading Prius forums and found that I should have conditioned the cells which requires the equipment I bought. The equipment allows the 6 1.2v cells inside each of the 28 individual cells to equalize better as over time 1 or 2 of those cells might not charge as well. Since a chain is only as good as it's weakest link the cells are on that same principle. The weak ones will slowly killing that individual cell. If the individual cell still doesn't hold a good charge after cycling it by draining it and charging it past normal capacity a few time it must be replaced. I am hoping after all this work the pack will be stronger then it has been in years and will extend the life of the car into the 250k range. The individual cells sell on ebay for about $40. Feel free to ask any questions since I think I have it mostly figured out now.

Eric ✉
Oct '14