How much voltage difference is acceptable with married batteries?

[conanthewarrior]

Hi people.

My batteries are always swapped each charge, to help try to keep them a balanced voltage.

The other day though, my Xcube 2 took a set of my newest 25R's to 3.2V and 3.5 Volts. Is this an acceptable range-or is that well far out?

Usually my batteries come out at most .2-.5 volts difference. I have used the 25R's since and they come out at 3.3V each, well 3.1 and 3.31V, so very close.

How much of a distance is acceptable with married batteries? It being the Xcube as well, and with the fiery incident last night makes me wonder about it's safety.

Anyone that could help would be fantastic.

Thank you, Conan.

 

[Neunerball]

I would only worry, if the lowest voltage on a battery is below 3.2V. Besides having married batteries, I'm also switching the slots in the mod, when I put the loaded batteries back in the mod. So, when battery 1 was in slot A, and battery 2 was in slot B, battery 1 will go in slot B, battery 2 will go in slot A next time.

 

[conanthewarrior]

I would only worry, if the lowest voltage on a battery is below 3.2V. Besides having married batteries, I'm also switching the slots in the mod, when I put the loaded batteries back in the mod. So, when battery 1 was in slot A, and battery 2 was in slot B, battery 1 will go in slot B, battery 2 will go in slot A next time.

Yeah thats what I do too, I keep a note next to my mirror on my wardrobe so I know which battery goes what side next.

Ok as long as its not below 3.2V, should be OK then yes? I have used them since, and they came out at 3.3 and 3.31V, so very close as usual.

I just wondered when it was time to worry about the voltage difference. Do you notice with a perfectly new set of batteries, for the first 10 or so charge/discharge cycles they come out identical, and then start to waver slightly?

 

[Neunerball]

It's highly possible, due to batteries not being 100% equal. One might have a slight different internal resistance than the other. The one with the lower internal resistance will discharge faster.

 

[conanthewarrior]

I was concerned with yet another detail to keep track of until I read a tip in some post.

I have a bunch of simple 2 cell plastic cases. The batteries stay oriented left/right when they come out of the mod, while charging, after charging. But I swap them L/R when I put them in the mods.

Easy.

That does sound good-the only thing is I would genuinely forget which one was the left battery with my memory lol! Its simpler for me just to keep a note pinned there-that will be handy for other people on here though.