What size cells?
08-24-2003, 01:37 PM
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What size cells?
The mah rating of cells determines the "size of the tank" of the battery pack. Thus, how long a pack will fly a given airplane and motor/prop.
If you're referring to your Slow Stick, you probably want 7-8 cells in the 800-1100 mah size. With the stock motor, an 1100 mah pack should give 10-15 mins. of flight.
If you're referring to your Slow Stick, you probably want 7-8 cells in the 800-1100 mah size. With the stock motor, an 1100 mah pack should give 10-15 mins. of flight.
08-24-2003, 05:09 PM
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What size cells?
I find the "size" you are referring to as quite confusing also.
I therefore don't try to remember them. I go by the mah rating. The higher the mah, the larger the cell is. Each mah rating corresponds to a cell size - AA, AAA, 4/5C, etc. I buy my cells by mah rating.
A quick browsing of any Web site that sells batteries will show the relationship.
I therefore don't try to remember them. I go by the mah rating. The higher the mah, the larger the cell is. Each mah rating corresponds to a cell size - AA, AAA, 4/5C, etc. I buy my cells by mah rating.
A quick browsing of any Web site that sells batteries will show the relationship.
08-26-2003, 09:56 PM
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What size cells?
but nimh are smaller and have the same mah. but u can use them in place of nicd of same mah and you'll end up with a lighter plane :-D or use nimh of same weight and get longer run time :-D
08-26-2003, 10:25 PM
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What size cells?
Here is a useful link giving sizes for batteries of all sorts!
http://www.powerstream.com/index.html
Good luck in sorting out all of it!
Cheers, Phil
http://www.powerstream.com/index.html
Good luck in sorting out all of it!
Cheers, Phil
08-27-2003, 11:17 AM
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What size cells?
Originally posted by red91sit
but nimh are smaller and have the same mah. but u can use them in place of nicd of same mah and you'll end up with a lighter plane :-D
but nimh are smaller and have the same mah. but u can use them in place of nicd of same mah and you'll end up with a lighter plane :-D
We are often pushing NiCd cells to their limits as far as draining current from them. If you replace a NiCd cell with a smaller NiMH of the same capacity, you often end up with a NiMH that can't handle the current (Amps) your motor/gearbox/prop setup is drawing. You will notice that you don't have as much power as you did with the NiCds. You will notice that the batteries are VERY HOT after a flight. You will notice that the NiMH cells will no longer hold a charge after a few flights like this.
As a general rule of thumb, you should replace NiCds with NiMH cells of the same PHYSICAL SIZE, that is a 2/3A NiCd should be replaced with a 2/3A NiMH. The advantage is not lighter weight, but additional flying time...
Originally posted by red91sit
or use nimh of same weight and get longer run time :-D
or use nimh of same weight and get longer run time :-D
08-27-2003, 09:11 PM
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What size cells?
Another rule of thumb - because NiMH cells, even of the same physical size as NiCd, have higher internal resistance [i.e. don't give up their electrons as readily], you should replace a 6-cell NiCd pack with a 7-cell NiMh pack, and a 7-cell NiCd pack with an 8-cell NiMh pack................
Cheers, Phil
Cheers, Phil
08-28-2003, 11:10 AM
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What size cells?
Again, another myth that won't die 
That used to be true with older NiMH cells, but the most popular NiMH cells these days actually have LOWER internal resistance than their NiCd counterparts. Adding the extra cell is generally not necessary.
KAN1050's, for example, have a punch that's as good as or better than the 600AR/600AE NiCds they'd be replacing.
That used to be true with older NiMH cells, but the most popular NiMH cells these days actually have LOWER internal resistance than their NiCd counterparts. Adding the extra cell is generally not necessary.
KAN1050's, for example, have a punch that's as good as or better than the 600AR/600AE NiCds they'd be replacing.
