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Old Oct 19, 2001, 01:06 PM
Use The Force Jim
Jim Walker's Avatar
Las Cruces, NM USA
Joined Jul 2001
2,341 Posts
Where are they??

So where do you get the CP1200 Nimh cells I've been reading about and how many amps will they give up without toasting?

Thanks in advance.....
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Old Oct 19, 2001, 01:28 PM
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SheldonYoung's Avatar
Vernon, BC, Canada
Joined Jan 2001
803 Posts
Are you thinking about CP-1300 NiCads? They're good for 25 A continuous and quite a bit more in short bursts.
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Old Oct 19, 2001, 02:44 PM
Use The Force Jim
Jim Walker's Avatar
Las Cruces, NM USA
Joined Jul 2001
2,341 Posts
Hmmmm.......

Could be, no doubt I am not well informed on the subject. Let me state what I'm thinking about and maybe that will help.

I've been running scenarios through Motocalc and without going into any details, Sanyo 600AE Nicads look really good as far as power to weight ratio. Motocalc says they'll give up the 13.5 my setup is asking for with no problems, but really short flight times. Now my experience with smaller planes is that going to Nimh's of the same weight as the Nicads you've been using will give you around twice the capacity and the same or a little less amps.

Sooooo...... I've been looking on the net for some Nimh's rated around 1200mah, .85 oz, able to deliver around 12-14 amps. I checked out the two online battery distributors I usually buy from and their stock of Sanyo's jumps from 800mah to 1600mah. Motocalc says the 1600's will toast at 13 amps draw and I know personally that the 800's can't do it. The distributors have some off brand 1000's and 1300's, but Motocalc doesn't list them and the distributors don't list their specs (internal resistance, etc....). They are a big question mark and my guess is that they probably won't deliver as well as Sanyo's. Sanyo's usually set the standard.

Thanks again.....
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Old Oct 19, 2001, 03:09 PM
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opualuan's Avatar
San Jose, CA
Joined Sep 2001
3,863 Posts
why not wire two packs of 800 nimhs in parallel? as long as they can do ~7 amps each pack you should be able to reach the required 13.5.

as for another source... what about firebirdxl packs? they look the same size as 600AE nicad's, and they're 900mah... they're running a direct drive speed 300/400 I believe in the firebird xl...
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Old Oct 19, 2001, 03:28 PM
Registered User
Rochester, NY, USA
Joined Aug 2000
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Many stores have the new CP cells now. They are CP1300SCR and CP1700SCR.

Here are a few:

Eflightpower.com

Diversity Model Aircraft

Eflightpacks.com

Hill's R/C

TNR Technical
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Old Oct 19, 2001, 03:57 PM
Use The Force Jim
Jim Walker's Avatar
Las Cruces, NM USA
Joined Jul 2001
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Thanks Greg and Sheldon. Apparently I was reading about CP 1300's thinking they were Nimh, but they are Nicads. They weigh twice what 600AE's weigh, so I guess I'll use the 600's. Any more weight on the plane and it takes it into a different flight envelope that I don't want. I guess 1300 Nimh's that can cough up that kind of amperage are still somewhere in the future......
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Old Oct 20, 2001, 07:40 PM
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West Middlesex, PA, US
Joined Jun 2001
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The firebird xl's bats are 6 cell sanyo 900 mah nimh's. The motor
on said firebird xl is a mabuchi 380 motor. I get 18 minutes flight
time with it. Matter of fact, I think the motor is 7.2 volt but I'm
not 100% positive on that.

dave...
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Old Oct 22, 2001, 03:29 PM
Use The Force Jim
Jim Walker's Avatar
Las Cruces, NM USA
Joined Jul 2001
2,341 Posts
I'm pretty sure your info is accurate Lucky. I've made a couple of 8 cell packs for people out of their two firebird packs when they graduated to a different plane. The cells are 900mah Nimh's, but they just won't give up the amps. We put one of the 8 cell packs in a S400 plane and it worked fine. We then tried it with a stock S480 and it worked, but performance was definitely off compared to using a pack of 600AE Nicad's. The motor I'm using is a Race 480BB and pulls even more amps than a stock 480. Motocalc says the 1600's won't work and I know the 900's won't do a stock 480, so I'm back to Nicad's.

Thanks anyway, Jim
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