ICE Charging tips.....
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ph2t
- bitPimp
- Posts: 1979
- Joined: Tue Mar 25, 2003 6:33 am
- Location: taco city
ICE Charging tips.....
Hey Sg, finally got off my arse to make a post about some features of the ICE that I've been using for a while now. I will post more as I get time and go along mate so this is only the begining. There is a bloody shitload of features that I don't even use yet!
Here's an example based on your typical GOOD set of 4, 800mAh AAA's found in mini-z's and xmods.
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AT HOME - Set ICE to charge at 0.6A, dV = 8mV, discharge at 0.9A, discharge to 1V/cell. Cycle 3 times, D->C order.
AT THE TRACK - Set ICE to charge at 2.4A, dV = 13mV, discharge at 1.6A, discharge to 0.7V/cell. 1 cycle only, D->C order. Use a fan to cool the batts during discharge/charge.
____________________________________________________________
What this does is that the ICE changes the way it looks at the batts when charging them.
When charging at home I can take my time, I charge at a nice light current and make the ICE "sensitive" to battery changes by keeping the dV value low. I'm not discharging the cells heavily and I do this a total of 3 times. Charge, then discharge. This helps keep all the batts in the "pack" in tune and as much feasible current is stored as possible.
At the track though I want to be able to cycle them as quickly as possible. To do this I need to throw a lot of current into them, but I need to keep the batts cool, so I have a small ex-PC fan sit above them to keep them cool.
When the batteries are cool they can take more current. I then push (up to) 2.4A through them. For a set of 800mAh AAA nimh's, that's about 3C in charge rate.
Heat is half the problem.. When batteries are charged at high C's, they will "peak" a lot stronger than usual. You have to compound this peak value across 4 batteries. If 4 batts in series have higher "peaks" than usual, then this value wil compound in size. Because of this I set the dV to a higher (per cell) value then you would normally set it to if you're charging a single cell at 3C.
I discharge them more heavily at the track and turn the per cell voltage way down. Most of you may not agree with this since 1V is the recommended value per cell. The bugger is at high discharge rates the batts will go below the 1V level and still have a bit of current still stored in them. Again, it's all about emptying all the batts well enough and quickly enough.
So, forced air cooling of the batteries and "de-sensitizing" the ICE against higher peak value will help you in getting your batts charged quick, like in 20 minutes......
These are my own values, don't consider them standards in anyway. Hell, I may even be wrong on some of my theory, it's been many years since uni, lol.... All of this comes with a heavy amount of attrition. Batteries treated like I have posted above have a life span of approx 8 - 12 months....
but they go like a muthafucker.....
ph2t.
Here's an example based on your typical GOOD set of 4, 800mAh AAA's found in mini-z's and xmods.
____________________________________________________________
AT HOME - Set ICE to charge at 0.6A, dV = 8mV, discharge at 0.9A, discharge to 1V/cell. Cycle 3 times, D->C order.
AT THE TRACK - Set ICE to charge at 2.4A, dV = 13mV, discharge at 1.6A, discharge to 0.7V/cell. 1 cycle only, D->C order. Use a fan to cool the batts during discharge/charge.
____________________________________________________________
What this does is that the ICE changes the way it looks at the batts when charging them.
When charging at home I can take my time, I charge at a nice light current and make the ICE "sensitive" to battery changes by keeping the dV value low. I'm not discharging the cells heavily and I do this a total of 3 times. Charge, then discharge. This helps keep all the batts in the "pack" in tune and as much feasible current is stored as possible.
At the track though I want to be able to cycle them as quickly as possible. To do this I need to throw a lot of current into them, but I need to keep the batts cool, so I have a small ex-PC fan sit above them to keep them cool.
When the batteries are cool they can take more current. I then push (up to) 2.4A through them. For a set of 800mAh AAA nimh's, that's about 3C in charge rate.
Heat is half the problem.. When batteries are charged at high C's, they will "peak" a lot stronger than usual. You have to compound this peak value across 4 batteries. If 4 batts in series have higher "peaks" than usual, then this value wil compound in size. Because of this I set the dV to a higher (per cell) value then you would normally set it to if you're charging a single cell at 3C.
I discharge them more heavily at the track and turn the per cell voltage way down. Most of you may not agree with this since 1V is the recommended value per cell. The bugger is at high discharge rates the batts will go below the 1V level and still have a bit of current still stored in them. Again, it's all about emptying all the batts well enough and quickly enough.
So, forced air cooling of the batteries and "de-sensitizing" the ICE against higher peak value will help you in getting your batts charged quick, like in 20 minutes......
These are my own values, don't consider them standards in anyway. Hell, I may even be wrong on some of my theory, it's been many years since uni, lol.... All of this comes with a heavy amount of attrition. Batteries treated like I have posted above have a life span of approx 8 - 12 months....
but they go like a muthafucker.....
ph2t.
People are mean to you because you're a fucking idiot.
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sg219
- bitPimp
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(I'm assuming the batts are Nimh's)
