Design - Leviathan Gas Goblin - Generator Mounting

[rcnut]

And that's why I use LiIon packs! No balance leads...

[gassed]

you cant charge a Lipo, balance it and draw current from it all at the same time. Raja would have to incorporate a microcontroller into his jewel to deal with all of that, and that would drive the cost up.

better to keep things simple.

[rcnut]

Same principle as a car battery...

[Sowa]

Don't quote me on this, but from my understanding if the current is low enough then a lipo does not need to be balanced.

Take a look at all the small hyperion lipos like those used on ultra micro planks, my 180 mah 3s and 240 mah 2s packs that I fly don't even come with balance leads from the battery manufacturer. Why? Even at a draw of 5 amps it's not enough to unbalance the cells. Ask hyperion about this yourself, and you will get the same response, the current is too low to unbalance the cells.

Because the generator supplies all the power the on board pack is there as a buffer. It only gets used until the generator is up and spinning. Therefore, the buffer pack sees a very low current.

If the output of the bec in the setup is ~8.4v there is no way to overcharge the pack, the potential coming out of the bec would have to be greater than 8.4v in order to over charge the pack.

[rbort]

And the generator is flexible, you can use it with all kinds of packs, from 4 cell NiCD/NiMH packs, to 5 cell of the same or 2 cell LiFE packs, to 2 cell Li-ion or Lipo packs. It won't overcharge any of them as you set the voltage to the peak charge level of the packs.

If you want to keep a lipo at a lower charge level so that over time it won't get damaged from staying closer to the top, you could lower the generator voltage down to 8v or 7.5v. The only drawback from this is that the battery is always have a lower charge level in it, which means that it will have less run time in the case where you need to use it.

-=>Raja.

[Sowa]

I still am curious about using a Optipower Ultraguard for a buffer pack. It would allow one to run at 8.4v and not have to worry about putting the pack in storage mode if it sits for too long, as the Ultraguard has a discharge circuit built in.

[KSHeli]

Originally Posted by mitsudriver274

I still am curious about using a Optipower Ultraguard for a buffer pack. It would allow one to run at 8.4v and not have to worry about putting the pack in storage mode if it sits for too long, as the Ultraguard has a discharge circuit built in.

Couldn't you add a larger capacity LiPO to the Ultraguard?

[Sowa]

Yes you could do that as well. It was just a hair brain idea of mine to use an optipower Ultraguard for a buffer pack. One of many, and probably not a good idea.

The cc bec that Raja uses in his kit is adjustable but only to a few select voltages, at maximum it outputs 8.0v. Im ok with storing my packs at 8.0v, so I'm keeping it simple. Let the backup solution be a back up solution lol.

[rbort]

The cc bec that Raja uses in his kit is adjustable but only to a few select voltages, at maximum it outputs 8.0v.

Actually no you can program it to 8.5v if you want as well, and also 12.5v if you're using it with a 3 cell Lipo or Li-ion battery.

-=>Raja.

[Sowa]

Really? I swear all the other values were grey and unselectable. I'll have to check out the software again.

[cruzroy]

gob gasser one-way bearing for jewel generator (2 min 48 sec)