Battery connection

[JRLocator]

I have 4 Power Queen batteries. The manual shows to hook each battery positive, one to another, and negative one to another for a parallel set up. Then to hook up each battery positive to the positive terminal block and each negative terminal to the negative terminal block. Isn't this a redundant hook up with a lot of extra cable material? Wouldn't it make more sense to just hook up each battery to the terminal blocks. That would connect all 4 batteries together in parallel, or am I missing something on this?

 

[pollenface]

You can do it either way

I have separate equal length cables to each of my 12v batteries from a busbar for redundancy (easy adding/swapping of individual 12v batteries) - cables must be created equally otherwise the difference in cable resistance will load/charge each battery differently

 

[JRLocator]

Ok. I do understand the loading. I have different lengths due to the area I have to install the control panel and the batteries. I did jumper the positive terminals together but when it came to the negative cables, it has become congested on the batteries and the terminals. I wonder in the manual hooking both ways is their way of maintaining the battery balance?

 

[pollenface]

I wonder in the manual hooking both ways is their way of maintaining the battery balance?

I think you're referring to balance as you would a series connection. None are necessary in parallel as that is the nature of parallel like two balloons joined together, however equal cable lengths from each battery to busbar is vital.

 

[JRLocator]

Ok that makes sense. Just realized that I am using 2/0 AWG wire. Very stiff and expensive. My batteries are 26.8 volts, 100AH. By the chart I can use 2AWG, {120A max). 2AWG will be better to configure and make all the same length as the longest one.

 

[BobK53]

Ok that makes sense. Just realized that I am using 2/0 AWG wire. Very stiff and expensive. My batteries are 26.8 volts, 100AH. By the chart I can use 2AWG, {120A max). 2AWG will be better to configure and make all the same length as the longest one.

2/0 wire comes in a 8 or 10 wire combination and a multi wire (perhaps 75 to 100 wires?). The 8 or 10 wire combination is indeed very stiff, but the true multi wire combination is very flexible. As far as I saw all 2/0 cable is expensive, especially if you need a lot of wire. Wiring from my inverters to my home cost me over $1,000 for 2 AWG wire. I hate to think about how much 2/0 or 4/0 cable would have cost for that distance.