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hah!The 17AH and 10AH batteries are actually labelled 35Ah?
Even though the total capacities on both sides of the equation are equal ?If the two 12V 35Ah batteries are equivalent then you don't need the smaller battery.
In any case putting two different batteries in the same circuit (series or parallel) is not a good thing to do.
One battery will drain faster than another.
You may do as you wish. With 4A load you should bank on only 2h operating service.Even though the total capacities on both sides of the equation are equal ?
Under equal testing parameters, the capacities of the three batteries are as shown.
Is that due to different IR's or what exactly?
It's not really about doing as I wish. It's a learning thing.You may do as you wish. With 4A load you should bank on only 2h operating service.
I tend to agree.I wouldn't count on that combination working well. The 17Ah battery will likely end up abusing the smaller ones.
Off base. Please try not to clutter the thread with nonsense.To continue this thought experiment - if you were to take a 17AH battery, and remove the plates, then cut them into two (using a hypothetical non-conductive saw) at 10/17 of the way along, then put each piece into a separate plastic tank, would you not have achieved the situation you describe?
So, provided that all three batteries are constructed identically with the same plates, strength of acid etc. I don't see hypothetically, why it shouldn't work.
This is my thinking. If the 7Ah battery reached a discharged state earlier than the rest, the 10Ah battery would try to charge the 7Ah battery. That would mean that the 10+7 combination would discharge faster than the 17Ah. Continuing to have a load would cause the 17Ah battery to force the 10+7 combination in to a reverse voltage condition. That would damage most batteries.I tend to agree.
But, why?
Ok. That makes sense.This is my thinking. If the 7Ah battery reached a discharged state earlier than the rest, the 10Ah battery would try to charge the 7Ah battery. That would mean that the 10+7 combination would discharge faster than the 17Ah. Continuing to have a load would cause the 17Ah battery to force the 10+7 combination in to a reverse voltage condition. That would damage most batteries.
This is EXACTLY what happened to the two 35Ah batteries I have in series.The main factor that has adverse effect on performance is battery internal resistance.
Let us begin with two identical batteries in series. When one battery degrades faster than the other, both charging and discharging characteristics will differ. In particular, the weaker battery will charge and discharge faster than the other which will accelerate its degradation.
If the batteries were matched. Even if you started with matched batteries, over time, one will become weaker than the other. That's when abuse of the weaker will accelerate.Do you think it would work if the bigger battery on the right was at 7AH capacity and the smaller battery was also at 7Ah capacity and the battery on the Left at 14Ah capacity?
I think that would be ideal.When batteries are configured in series it is better to charge them individually.
I have two 12V batteries in my lawn mover. I opened the battery pack and brought out a connection to the junction between the two batteries. Now I can charge each battery separately.
by Jeff Child
by Aaron Carman
by Aaron Carman
by Aaron Carman