LiFe Batteries - RC-Monster Forums

what do now · **LiFe Batteries -** 12.16.2009, 01:33 PM

Hi

Can someone give me a run down on LiFe batteries. I currently use 2x2S LiPo's for my trucks and know nothing about LiFe, but they are supposed to be a lot safer.

Any Pro/Cons. Finding it difficuly to get any good informative threads on it.

Thanks Guys.

lutach · 12.16.2009, 01:47 PM

The LiFe chemistry is safer, but any battery can fail if not used correctly. The only downside so far for the LiFe batteries though, is the voltage and they tend to be a little heavier then similar lipos.

JERRY2KONE · **Pros -** 12.16.2009, 08:49 PM

The pro's in this is that the chemistry is technically safer(will not catch fire) and there is no need for an LVC, because you can run them until the power drain is noticable. From the things that we have seen posted in here people have said the the punch is slightly lower from the LiFe's. Seems like a good trade off for less worries about the safety factor.

what do now · 12.17.2009, 02:36 PM

OK interesting, thanks.

What is the voltage of each cell then??

lutach · 12.17.2009, 03:07 PM

Quote:

Originally Posted by what do now

OK interesting, thanks.

What is the voltage of each cell then??

Well, that's an interesting question. Most of the manufacturers I know of LiFePo4 cells says the maximum voltage on them is 4v, but under load it should be around 3-3.6v.

what do now · 12.18.2009, 06:28 AM

So what you make up for in weight(over Lipo) you lose in a little voltage.

_paralyzed_ · 12.18.2009, 06:50 AM

Quote:

Originally Posted by what do now

So what you make up for in weight(over Lipo) you lose in a little voltage.

nope. The lifepo's are heavier for a given capacity, you must have misread that. Lipo's are lighter, have more voltage and more punch.

Lifepo's are heavier, have less voltage(and therefore less punch)

In addition to lifepo's being safer (can be discharged without an LVC, won't catch fire if overcharged) they are generally expected to get 1000+ cycles (lipos are expected to get 200-300 cycles) and lifepo's can be charged as fast as your charger can charge it. (many lipos are limited to 1c charging)

In the end it's personal preference. I run lipos because they are faster and take up less space.

what do now · 12.19.2009, 10:26 AM

Oh ok, yeah misunderstood.

Thanks.

simplechamp · 12.23.2009, 01:27 AM

So is there any detriment to the life of a LiFe pack (no pun intended) by running with no LVC? I am about to start running my Turnigy LiFe packs in my TC3 and wasn't sure what to set the LVC at, or even if I should use it at all. At what voltage does the "punch" start to drop off noticeably?

JERRY2KONE · **Hype -** 12.23.2009, 02:26 AM

The hype from the manufacturers states that NO LVC is needed with the LiFe packs. When you see the power begin to drop off of the battery(vehicle slows down) turn off the ESC and charge up the packs. Simple as that. Plus 1,000 charging cycles. Can't beat that with a stick.

johnrobholmes · 12.23.2009, 02:44 AM

You should still use a LVC, IMO. Every time you go below 2v per cell you will lose some capacity and cycle life. Of course a battery manufacturer wouldn't suggest a LVC. You won't ruin them, but you will have to come back for new packs quicker.

simplechamp · 12.23.2009, 03:44 AM

A few datasheets I found online also suggested around 2V minimum discharge voltage. I'll set my LVC to 2.2V per cell. I'm not going to sacrifice the life of the pack just to get an extra minute or two of runtime, especially when the "punch" will be gone anyway.