Lipo V Life

[Carole_MH]

Just a quick question on batteries.

With life batteries coming to an affordable price what are the comparisons to lipo and the advantages/disadvantages. I know the safety issue was a big thing a few months ago regarding charging etc.
I suppose what I really need to know is :-
a) will a 3600 35c 6.6v life pack be as good as an equivalent lipo pack I.e. Run time, recharging between races etc.
b) can the life packs be recharged as many times as lipo without losing performance
c) will 6.6v be enough to power rx, servo, motor and pt for a full 6 minute race
d) if the voltage drops will it just stop as per lipo, or slowly run down as per nimh, also if the voltage drops does it damage the pack as per lipo, therefore requiring a voltage cut off on the esc etc.

Any advice would be appreciated as I fancy taking a look at the life batteries as and when the time comes to replace my lipos.

Carole

[warped]

Main advantage of life is the chemistry is safer so they represent less of fire risk.

Main disadvantage is that they are lower voltage than lipo so will be a lot slower, unless you bolt in faster motor.

If there are no motor limits in the class you run and you can afford to upgrade motors as well then they may be worth considering.

If you race a fixed motor class, then lipos are the only way to go.

[SlowOne]

Run time and re-charging rates will be equivalent. As warped says, the voltage will be less so the car will be slower. Not recommended for Stock classes, just 'motor up' if you're running Modified.

Yes, as it stands, LiFe and LiPo have an equivalent life.

6.6v is enough to power all your electrics. They all require 6v minimum, and even under load you should be over that. 6.6v is the fully discharged voltage, which is still well above the 6v fully discharged NiMh we used to use!

Unless you use a cut-off the battery will go to zero and be damaged, just like LiPo. However, you can't use a LiPo cut-off as that will be 7.4v. If you use a Tekin speedo you can select a custom cut-off voltage, but all other speedos I know of, and specialist cut-off devices, will be at too high a voltage. Don't run the cells flat, you'll wreck them - use a cut-off.

For now, I would suggest that LiFe is good for Club if you can motor-up, but not for competition. They are great as receiver packs though! HTH

[MRD]

I can see them finding a home in the touring car market to replace 5 cell racing.

[MattW]

The info that we had from one of the well known cell "manufactures" was that deep discharge was much less of an issue with LiFe than it is with LiPo.

I tested one in touring car last summer - was comparable to 5 cell NiMh, which is what we were running for mod at the time.,

[mark christopher]

Originally Posted by MRD

I can see them finding a home in the touring car market to replace 5 cell racing.

5 cell mod is dead isn't it ?

[MRD]

But did it die due to Lipo's becoming the better power source and being restricted to 7.4v?. Dead or not it opens up the posibilty to run a lower voltage class, possibly for indoor TC racing without the bother of cells

[RogerM]

Speed Passion ESCs also have variable cut off voltage.

I am looking at LiFe as I'm not and never have been happy with the way LiPo delivers it's power ... I'd much rather a softer power delivery from the cells and motor up to get the same speed personally.

As soon as LiFe is a viable option for me (i.e. good quality saddle packs easily available from major sources) I will move over. Can't wait to get rid of LiPos if I am honest for the same reasons the touring car boys, and some off roaders, went to 5 cell NiMh!!!