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Mitchell
2012.09.15, 02:07 AM
Hi,
I started to test LiFe R246 batteries in my mini-z.
Increasing of power is significant, but I still miss some experince what motor I can use and what maxi current for charging LiFe batteries I can apply.
Please, if you have some experience, gime me info:

1/ charging: in the manual for LiFe R246 is written: "max.charging current 0,8A". In this case the time for charge is approx.30 minutes, so it is not so fast and I must have 2x2 packs for our races. Can I charge it by higher current to use only one pack without removing it from the car ? What current do you recommend ?

2/ before charging, is it necessary to cold LiFe batteries after finishing the precedent race or can I start to charge it immediatelly ?

3/ R246 has special motors for LiFe batteries, I have one, but perfo of the car is much better with another motors (ATM Ad, ATM T2 Plus 35T 17mm, etc.). Can I use this motors for higher LiFe´s tension then NiMHs have ?

Thanks for sharing yours experience

reaper
2012.09.15, 04:23 AM
Charging : stick to the recommended charge rate ,the battery chemistry is very different to "normal" batteries so fast charging at higher amps will ruin them and may even explode
.
Motors, I'm guessing the recommended motor is matched to the li-fe output , running a faster motor means higher amps that the cells may not be able to deliver ( c rating) this can damage the batteries
Hope that helps

Felix2010
2012.09.30, 03:39 AM
You should be fine running any PN, ATOMIC, or other aftermarket, off-the-shelf, machine-wound motor with the Mini-Z LiFe cells.
***You should use caution with custom hand-wound motors and Lithium, especially hand-wound motors with Less-than 35-Turns, which can be very fast and have very high Amp draws...

The only "machine mass-production" Z motors under 35t that should be fine to run with LiFe would be PN's 33t and 32t MOD motors, which still have reasonable current-draw rates and will run well with Lithium cells. The AMp draw on the Atomic AD is low, and even the T2 & T2+(17mm Ver) have only medium-tomedium/high Amp draw also... Any motor as long as it is 35t and above should not hurt your LiFe cells...

The more-important aspect of LiFe is the charging and maintenance. I would stick to the recommended charge rates for best life. And, you won't run the risk of burning-out the cells from too-high-amp charging and/or discharging.

Also, I would make sure to keep the LiFe cells near-charged (Do not store these cells for weeks or even days with the cells at low-voltage - If the voltage dips too low,for too long... Lithium cells can & will incur permanent damage.

Hope this helps a little:)

ByronF1
2013.05.20, 07:06 PM
Does anyone try these batteries? how much do they long? are easy to drive? do they last ? compared with NiMh, what you say... ?

Sinister_Y
2013.05.20, 08:12 PM
most of us run them at my track. they last around 12 min. so, have a set for each heat. they are awesome compared to nimh. really good power and they last for a while in term of life of the battery (not to be confused with charge). we run atomic round can or me personally i like the R246 Li-Fe motors (hi torque and hi speed versions). It's plenty fast. Keep in mind once you notice the car getting slower, pull it off the track as you can kill the battery unless you are running mR03VE with the correct setting for Li-Fe.

ByronF1
2013.05.20, 08:47 PM
thank you, did you tried with other motors...? like PN 33, or atomic?

machgo5go
2013.05.21, 09:15 PM
thank you, did you tried with other motors...? like PN 33, or atomic? Picked up some in Japan last year since not hot selling item so it was discounted heavily.
I balance charged these LiFE in sets of 2 which made them much more equal as they drop off together. As for PN 32 T motor as we run open class every friday night, the motor almost burn up these LiFe. It ran short time of quick burst in the beginning then drop off quickly plus hot as hell. These LiFE are more suitable for Brushless VE or more for 50T or so IMO.