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[glenpens]

Which batteries would you use in a rc buggy. 7.2v NICD or NIMH
Glen

[Colin Bishop]

NIMH seems to be the way to go these days. NiCads are being phased out anyway.

[glenpens]

Colin
Thanks for the information.
I have just been told it looks like NICD batteries are likely to be banned
Glen

[HS93 (RIP)]

Nicads only go to ABOUT 2200 mah where as Nimhs go to 4500 mah and above  IN sub"C" size.  Peter

[justboatonic]

Yep, definitely Nimh's unless you want to run brushless motors then I think you must use Li-poly packs and dedicated speedo.

[Mankster]

Brushless motors will work of any battery, though you do need a dedicated ESC.

[alan colson]

I spoke to John & James (Model Power) at the Alfold show recently and I think they said nicads will not be available after July next year

[grasshopper]

Get an engine....tempermental, noisy, smelly (in an addictive sort of way) and loads of fun - and to keep it runnning bung in more fuel...non of this waiting to recharge business

[J.beazley]

So whats everyone to do when they do ban Ni-Cds  ??? surely the price of the higher Mah batterys will come down to a more affordable market.

on the cheeky side all unwanted Ni-Cds forward to me i can make good use of them 

Jay

[justboatonic]

Brushless motors will work of any battery, though you do need a dedicated ESC.

Is that right? I thought brushless motors wouldnt work with a 'normal' ESC and required a brushless ESC which only worked with Li poly packs.

[Welsh_Druid]

Brushless motors will work of any battery, though you do need a dedicated ESC.

Is that right? I thought brushless motors wouldnt work with a 'normal' ESC and required a brushless ESC which only worked with Li poly packs.

I just checked this with my RNLI Hovercraft which has Brushless motors and the special Esc. for brushless motors.

I tested the motors with an 11.1v Li - poly (their usual supply) and then with a seven cell (8.4v) Nimh pack.

The motors run fine on both,  but of course slower on the Nimh.

Don B.

[tobyker]

My airboat goes just fine with a brushless bell motor and 7.2 Nicad. However I was warned by All-Electric R/c who supplied the motor and ESC that the ESCs are set up for the higher voltages of LiPo batteries, and to cut off at 3 volts per cell or so to protect them, so that I might not get much of a run if I only started with 7.2v. This may be why people associate brushless motor/ESC combinations with LiPos, since the manufactureres assume that you are going to use them in flying machines which use LiPos for lightness. I think if I did use a LiPo in the airboat it would take off ; as it is I get as long a run as I can handle.

[White Ensign]

There is no difference for the motor if the power comes out of an Li-Po or Nicad/NiMh or dry-cell.....DC is DC, you only need a different speed-controler.
Also it is not possible to connect two brushless motors on one speed-controler.

If you compare the Nicads to NiMh you will find on the same size the NiMh with about two times the capacity, no memory effect and a better line of power until the end. If you calculate it now, you`ll find the NiMh (even if they are a bit more expensive) a better value for your money.
I.e., Nicads are in Sub C available up to 2700 mAh, the same size of NiMh are about 4400 now. Take the price and compare it, plus the advantage that the memory-effect in Nicads break them much earlier in their service, plus the price to get the same effectivity to come up to the NiMh.....- you`ll easily find it worth it.
Just my pennies.......


Jörg

[Stavros]

If you want a cheap place fro batts try the component shop no connection just a satisfied customer Stavros

[wombat]

You don't need a LiPo for brushless motors - anything with the right voltage. However if the weight is an issue the LiPo gives the gretest energy density.

I think also, the peak current that a LiPo source is much higher than either NiCd or NiMH battery. The problem gets worse as you increase the capactiy of NiMH cells as the internal resistance of the cell goes up becuase of the way they boost the capacity - by increasing the surface area of the electrodes.

Wom

[justboatonic]

Thanks for clearing that up folks. You learn something new every day!

[White Ensign]

Wom, don`t forget to say that you need a special charger for Lipo`s and that the might explode if they run in service under their nominal voltage.....
Lot´s of users of mobile telephones, Laptops and Notebooks may tell a story about it....

Jörg

[wombat]

Good point Jorg (sorry about the missing umlaut)

Most appliances that use LiPo have a shut-down that prevents startup if the battery voltage is too low.

LiPo batteries need a properly designed smart charger - don't try to use a SLA charger or NiCd/NiMH charger unless the fire insurance is up to date.

Here is a link with more info:

http://www.powerstream.com/li.htm

Wom

[Martin (Admin)]

Just for reference ......

http://www.modelpower.co.uk/

http://www.component-shop.co.uk/index.html