I fly my parkzone micro t-28 every day I can weather permiting,now that I learned to fly on the champ and super cub, and ohh yeah this site is the best it helped me learn so well, so just a shout out for all the helpful info. Okay here is my problem im stumped the t-28 came with a 120mah 3.7 volt lipo and I have two eflight 150 mah 3.7 volt lipos. Okay they all used to get about six to five mins flight time easy, now the newest one I got four weeks or so ago is fine and gets plenty of flight time but the one the Trojan came with and the other eflite lipo the bad ones get about two minutes,three tops, I don't understand. the one eflight battery I got four months ago might be old cause I bought it as an extra for the champ, as I wanted more flight time to learn three channel on the champ, so that one I guess I understand could be old. I sold the champ so I don't have the original hobby zone 150mah lipo. I don't understand why they die so fast?, more so the one the Trojan came with cause I have had the plane for two months at most, what is the deal both batteries charge real quick too except the one that is good that still takes thirty mins or so. So what am I doing wrong when I finish flying I wait till there completely cool then charge them again but sometimes i don't fly and they stay charged are u not suppose to fully charge the flight batteries even if u don't fly the next day. I rarely if ever fly the micro Trojan and hit LVC. What could be the problem? what am I doing wrong should I not charge them till full?, until I fly again because I have left them fully charged for days due to bad conditions how should I fix the lipos? or in the future store and maintain the little 3.7 volt eflite 150 mah batteries. Please help me I'm so sorry for the long TEXT AND RUNON SENTENCES, some info on making these batterys last would be so useful, i used to get out there to the field and fly for thirty mins, now since I only have one battery im out there for ten mins tops. thank u for your responses Sorry again for the long text it's also oh p.s. It's not even cold out yet im stumped

There are several things you can do to prolong the life of a LiPo, but eventually they all wear out -- some quicker than others. Sometimes there's a correlation between what you pay and how long they last, but not always.

But steps you can take include:-

1. Don't run your motor until the battery's flat -- time your flights so that you use only about 80% of its capacity.
2. Don't store your batteries for long periods with a full charge in them.
3. Don't charge them too fast.
4. Don't subject them to too many amps discharge rate.

With something like the PZ models, which presumably come with their own chargers and motor/prop/battery, there's not much you can do about 3 and 4. And, personally, I don't usually comply with 1 and 2 with the small batteries (2S 800mAh) in my small heli either; though I'm much more careful with my larger, much more expensive ones. My small batteries last anything between about 50 and 200 flights before I consider I need to replace them.

My oldest LiPo at the moment is a TP Prolite 6S 2600mAh pack which I use in my T-Rex 500 heli. I bought it in October 2008, it's currently had 61 flights on it, and it still gives me 7 minute flight times for 80% capacity. I don't want to start a competition for oldest working LiPo, but that's just an illustration of how a good quality one that's been looked after in accordance with the above "rules" can hold out.