What Novak system for my e-revo running on 7 cell nimns?

[TexasSP]

Lipo do not just spontaneously combust sitting around. Handling them is no different than any other battery. There is actually more potential for nimh to cause fire than lipo as nimh heat up quite a bit when charging while lipo stay almost at ambient temps. The cutoff is easy, all you do is set the ESC to cutoff for whatever voltage is correct. This is usually 3.0 to 3.2 volts per cell.

Don't let lipo scare you, the horror stories are mostly from stupidty. Take your time and don't rush getting into this. This forum is a great place to learn and you are better off buying once the right way than multiple times the wrong way out of fear of the unkown.

[martin34]

Thanks mate and for the advice i see what you are saying.I might go lipo in the future once i have learnt a bit more about it.Say i set the cut off point to 3.0 or 3.2 like you say does the car cut out when the batteries get to that voltage?(i gather they do)then do i just recharge them again like i would with nimhs?

[JThiessen]

You would charge and balance them. And yes, lipo cutoff's will cause the car/truck to stutter and stall.

Going lipo right off is a much steeper cost, since you'll also need a charger that can do lipos. I understand the fund limitation. Nothing wrong with taking small steps into this. There does tend to be some amount of arrogance on forums relating to "go 100% into it, or dont bother"....if you only have so much $$$, dont put yourself in debt due to some guy on a forum telling you what to do. Tex was correct that there is one brand of Lipo that can be had at Nimh Cell cost (Zippy), and quite a few of us run them. There is a sizable performance advantage to them also.

If you must do this in stages, you next purchase should be a decent charger than can also do lipo's, so you'll be set when you do go that route. The better chargers will also take better care of your Nimh's. Those cheap chargers are probably the biggest cause of Nimh cells going bad (IMHO).....A superbrain is probably one of the better entry level chargers around 100 bucks (I'm sure there are a few others) but it will need an external balancer when you go lipo, Hyperion is probably the best of the mid level ($200 and up) with built in balancers.