What about direct Lipo usage (2S , 7.4v ) on current ignitions for gas engines ?
If you have two versions available , one for 4.8 NiCD/NiMh and other for LiPo 2S 7.4v , what's your choice ?

Thanks ...

Rcexl ignitions are rated 4.8V to 6.V and draw between 150mAh and 350mAh in mixed flight, depending on RPM from a 4.8V pack and approximately 25% more current from a 6V pack.
The older ones couldn't handle anything over 6 volts, or their circuitry would fail. I believe the latest versions can actually handle 5-cell NiMh / NiCd packs but draw more current.

Given the low current draw and the 6V absolute limit, I personally don't see any reason to use anyting other than a standard NiCd / NiMh 4.8V pack.
You get a very good flying day out of a battery as small as 800mAh but most use 2,000mAh Eneloop packs.

I know current RCEXL specifications.
I ask for preferences for the ignition battery.

Thanks

Al gave you the straight talk already? I thought he answered your question?

Sorry for my bad english. [] Maybe i didn't explain my question .
I know all current RCEXL ignition specifications. Many thanks to apalsson for their reply.
I'm asking what will be your choice if you can get ignitions for differents batteries.
One version for NiCd 4'8-6V AND another cdi ignition version for 6v-7.4 V

Regards

It would be ideal if they could operate on anything from 4.5 to 9 volts. That covers 4 cell Nicad/Nimh through a fully charged 2 cell Lopo. I have expressed this to Xu Liang before.

Me too

Regards

OK, anything but a lipo for a gas powered model
There is a simple fix if you want to run a CDI ignition significantly above 6V, that is to use a regulator on the input. For a CDI ignition to work reliably from 4.8V to 8.4V reliably, it would have to have an internal regulator, there is no other way to do it. So why make the module more expensive when most users will use a battery of the correct voltage, or just use their own regulator.
Pete

I would have a strong preference for the latter.<br type="_moz" />

Given a choice between the two, I would prefer the 4.8V version. NiCds are very reliable, very durable, inexpensive and last for years without worry.

-Ed B.

Actually, I second that.
Also because I see little reason to use high-current release batteries like Lithium (LiPo / LiFe) to power a device that draws mere 100mAh - 350mAh in mixed use.

And ... the "single charger" argument doesn't cut it for me either because most decent modern chargers will happily charge your NiCd/NiMh ignision battery on one output while they charge your LiPo/LiFe receiver batteries through another output

Heck I would go for the 2 cell lipo, The ignitions are cheap enought to get replacements.