Question on a transmitter battery. I have always used AA's for my radio, but thinking of switching to LIFE. We all know that lipo & life packs are not supposed to be stored fully charged, or they puff. My question is if I charge my radio battery at the start of the race day, use it all day and then store it, how much could it have drained? How do the radio batteries not puff from storage? Is this going to be another battery that I have to discharge at the end of the race day?

I've never heard of Lipo or Life batteries puffing due to storage at high voltage. Puffing is usually the result of hard use.

The "problem" with storing lithium batteries for longer periods of time is the effect that the voltage they are stored at, impacts their capacity. The higher the voltage, the bigger the impact. But you don't want to store them too low or the voltage might drop too low during storage and ruin them.

I use a Life battery and don't worry about it. If after 4 or 5 years it's not usable anymore, I'll just buy another since they aren't that expensive. Also I like the fact that I don't have to worry about self discharge.

Get these http://www.hobbyking.com/hobbyking/s...y_to_use_.html
along with the charger.

Inexpensive, no mods need to be done and they last a long time before needing a recharge.

Why switching to LiFe or LiPo ?

If it is because they hold the charge much better then I would advise to get soem Sanyo Eneloop batteries.

Thought it would be cheaper over time.

Only problem with rechargeable NiMH's is their nominal voltage is 1.2V.
5.0V for your Tx is pretty low to start with.

The NiZN batteries I linked to measure 1.6V each and I regularly start off with 7.0V+ on my DX4R after a re-charge.

Been using Nimh for years in my 3R with great results. Still using the same set after 5 years at least.

I have a 3S lipo pack I use for my futaba 3PK. Its easier to charge that than 8 AA batters.

They have a higher capacity than AA batteries and I find them generally more reliable. Never noticed any buffing with them and I had it for years.

I agree, Low Self Discharge / Ready To Use nimh cells make great transmitter batteries. Nearly all of the advantages of lithium without the drawbacks. Hold charge well, easy to charge with most RC chargers, no balancing plug to mess with, work well in cold weather. I've used the Tenergy Centura version for several years, have never ran down despite rarely charging them.

I do not use LiPo for the TX but arround me I have seen many LiPo TX batteries failing. I think charging w/o balancer could be the reason of this, a lot op people do not think a balancer is needed
The Eneloop are wonderfull batteries. As mentioned they are easy to charge without balancer cable so you can charge them through the TX charger plug and hold the voltage as if they are LiPo's.

Most of the time if there is a AA battery holder you can take out the holder and place a 5cell AA battery pack.

I just switched to the NiZn batteries for my DX3 and DX4. They have a normal voltage of 1.5 instead of the 1.2 of NiMh/ NiCd. I did a test run a couple weeks ago and left them on from the time I got to the track until I packed up 10 hours later and went from 7.1 volts fully charged to 6.5 volts. Took about 35 minutes to fully recharge.

Check them out on E-bay ( possibly other places). 4 2500mAh batteries with charger and free shipping for $25 is not bad. Just bought 4 more last week for my daughters radio.

I've been very happy with LiFe and LiPo transmitter packs. I can't see myself going back to AA-sized NIMH batteries. The ability to go all day without charging once is great. Also, less weight.

I haven't tried the Nizn batteries, but I have a set on order.

As for as storage, I use my PL8 to take the packs to storage voltage after every session. I've never had one puff in storage.