Aero330LX
Posts: 450
Joined: 4/6/2002
From: None, USA
Status: offline
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I think your post is more misleading actually. Firstly, yes I do in fact use the new Li-Ion packs, and have some numbers written down that should prove very interesting to you. Flight time, 12- 15 minute flights on one single charge. Please don't try that with a 2800 NiCd...it could be a long winter if you know what I mean. Hassle... No need for cycling, no problem with amp output when you use the proper pack...i.e. NO one I know uses a single 2 cell pack in a high current demand sysytem. Here's some numbers... A 35% airplane with 7 servos draws 4.5 amps tops. A 2800 pack uses 4 cells whick gives 7 amps...plenty of margin. The Li-Ion cells are extremely reliable, not to mention the packs built with more than 2 cells are redundant...meaning there is NO posibility of a crash because a cell dropped out. You land...you check, and then you see it. Regulators? Have you had one fail lately? Have you ever seen one fail. They are extremely reliable. The only thing I could think of that could cause problems (not a failure, but a user mistake) would be a connector coming loose, and that would be caused by the user not secureing it properly. Do they fail? yes, EVERYTHING fails, however, it's highly unlikely. Where you got the figure for 400 cycles I don't know, but that is not the figure that has been shown through testing, and is not the figure the manufacturer of the cells suggest. I assume that may have come from Powerflight...they have had issues keeping the packs balanced. No such issues with these packs. As for the regulator, absolutly...I wouldn't consider putting 8.4v to my Rx.'s, so yes it is needed. As for non-linear again, absolutly. I wouldn't want to see a straight-line (linear) dropoff. The NiCd's have a plateau yes, but the kicker is the amount of flight time you get before that big drop. That time is approximately 4-5 flights, then you have to charge. After 12 flights with the Li-Ions I simply go home...it's dark. The batteries still have flights on them and I recharge. This is good because they are never "pushed" to the limit. Overcharge, and discharge is a non-issue. Yopu simply plug the correct charger in and it cuts at the proper voltage. The circuitry is built right into the battery to control this. Disharging below recomended can only happen through the users fault...it is not a fault of the battery. If you leave the switch on and they get to 5.5v, yes they will shutdown. For those that have the habit of leaving the switch on (personally I don't know many) there is a cutoff that can be bought to prevent damage to the packs. This statement I really don't have a reply for, except that while I've been using them I have found them to be superior in every way. The above re: should confirm that. As for setup, 3 2800 are a little much...Actually a 1900 on the IGN and 2 2800's are sufficient. with that the IGN will last as long as the flight batteries...maybe a tad less which is desireable, but it's very close. As I said above, haven't been able to fly enough in one day to bring them down to the no-fly voltage. Total price for my setup was around $278 dollars. Add a 5.1v IGN reg in there though...I already had one of those on hand. Don't think that reg will cost 200 bucks though. Try some of these...you'll find they work just like they're supposed to...just like I did. Just charge them, fly them, check them, and when you get tired, charge them again. As long as you check them every flight you'll be fine...no need for paranoia.
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