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Old 12-20-2018, 03:03 PM   #10
Ka_sea_ta
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Quote:
Originally Posted by twistedtree View Post
I'm pretty sure you still lose half the capacity, or more accurately, only half the capacity is usable. The reason is because one of the 2P sets is now 1P, and it will drain twice as fast at the other 2P sets in the series string. When the 1P set becomes drained, which will be at about the half-way point for the rest of the sets, it's voltage will drop and quickly bring the voltage of the whole bank down. Essentially you end up with 0P for one if the sets because one cell is dead and the other is drained.

I think if you look at the firefly battery there are 2 independent 2 volt cells in each case. I referred to an individual cell failure not the entire battery. Batteries can fail in all kinds of ways but electrically they will these failures will either create a higher resistance or lower. if it is low enough likely there will smoke or lots of heat... If the resistance or the ability to accept a charge goes higher or opens entirely instead it effectively reduces the the amp hour rating from 900 to 450 just for that battery. in discharge mode as the voltage begins to drop on the remaining good cell I believe that the rest of the bank will try to replenish the electrons in that cell as well as servicing what ever load there is. This is just the same as having gcs and l16s in a house bank Amp hour capacity in this case is not the weakest link but the average link..
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