well with the delta T, you gotta have whatever part of the charger that detects heat right against the batteries. if you bury it somewhere in the middle of the pack, i think it should work.
i dont really know though... why dont you ask this in the powerizer forum?
Battery complications
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blackbox_dev
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Thank You! I'm glad that people are finding it usefull!
Yes, I like the wiki a LOT better then the previous format of Portable Street.
About the batteries: I'm not sure what your asking, but isn't connecting recharables together in parellel bad because they will try to charge each other? And if you have 2500mAH recharging a battery that's sure to do some damage.
Don't flame me if this is tottally unrelated; I did my best to try and understand his question.
Yes, I like the wiki a LOT better then the previous format of Portable Street.
About the batteries: I'm not sure what your asking, but isn't connecting recharables together in parellel bad because they will try to charge each other? And if you have 2500mAH recharging a battery that's sure to do some damage.
Don't flame me if this is tottally unrelated; I did my best to try and understand his question.
I'd imagine right now you wish you were a cuttlefish...
well the problem with detal v is that theres so many cells, all having their own delta v spike at slightly different times, that it all just kind of gets muddled up.
about batteries charging each other, "massive current spike" is not a very good way of putting it at all. the current would be proportional to the difference in voltage, probaly less than 100mA. (random estimate)
as far as i can imagine (and this is just me imagining) i cant see why having them charge each other would be a problem. i mean - they are rechargable right? using batteries to charge other batteries is a perfectly valid scenario, its not like it hurts them or anything.
if one of your two series packs can power your portable (ie they can handle the current draw), and you are worried, just make it so you can independantly switch one or the other one on. when one is dying, turn the other one off first, then turn the dead one off... it shouldnt cause the system to reset or anything.
about batteries charging each other, "massive current spike" is not a very good way of putting it at all. the current would be proportional to the difference in voltage, probaly less than 100mA. (random estimate)
as far as i can imagine (and this is just me imagining) i cant see why having them charge each other would be a problem. i mean - they are rechargable right? using batteries to charge other batteries is a perfectly valid scenario, its not like it hurts them or anything.
if one of your two series packs can power your portable (ie they can handle the current draw), and you are worried, just make it so you can independantly switch one or the other one on. when one is dying, turn the other one off first, then turn the dead one off... it shouldnt cause the system to reset or anything.
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superdeformed
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"Parallel arrangements suffer from the problem that, if one cell discharges faster than its neighbour, current will flow from the full cell to the empty cell, wasting power and possibly causing overheating. Even worse, if one cell becomes short-circuited due to an internal fault, its neighbour will be forced to discharge its maximum current into the faulty cell, leading to overheating and possibly explosion. Cells in parallel are therefore usually fitted with an electronic circuit to protect them against these problems."
From: http://en.wikipedia.org/wiki/Battery_%28electricity%29
The latter portion of that is probably what I was thinking of when I wrote that other post, so yeah, "massive current spike" was definitely not a good way of putting it for normal conditions. There are still problems associated with doing it though.
Anyways, as for chargers, if you don't mind spending some money you might look into R/C peak chargers as an alternative to the wall warts. A lot of them just have spring clip terminals for the connections, so you can hook them up to pretty much anything you want. I believe most of them are -delta V chargers, but they seem to do a significantly better job at detecting a full charge than the cheap wall warts. Of course, you would still only be able to charge one set of cells at a time with these; making your own charger that charges them in two seperate circuits might be the way to go.
From: http://en.wikipedia.org/wiki/Battery_%28electricity%29
The latter portion of that is probably what I was thinking of when I wrote that other post, so yeah, "massive current spike" was definitely not a good way of putting it for normal conditions. There are still problems associated with doing it though.
Anyways, as for chargers, if you don't mind spending some money you might look into R/C peak chargers as an alternative to the wall warts. A lot of them just have spring clip terminals for the connections, so you can hook them up to pretty much anything you want. I believe most of them are -delta V chargers, but they seem to do a significantly better job at detecting a full charge than the cheap wall warts. Of course, you would still only be able to charge one set of cells at a time with these; making your own charger that charges them in two seperate circuits might be the way to go.
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blackbox_dev
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