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TomiGun
12-24-2005, 02:56 PM
I fly lots of R/C planes. Currently using Lithium Polymer, not Ion technology. aka Lipoly.

Each cell is 3.7v , so 2 in series or 2S pack will be 8.4v.. This pack is between 9.6v and 7.2v regular battery packs. Weights heck of alot lighter and it's VERY small so you can fit it in tight spots.

I will probably buy a pack and try it out on the gun. If it works, I will let you guys know.

Just in case if you didn't know, These batteries depending on the price you pay will put out 12C and up to 20C. That's 12-20 times it's output. So a 1000mah pack will put out 10 amps. I don't know how many amps a airsoft gun puts out but that's alot of power for a small battery. Plus, you get 2-3 times longer run time.

The downside on Lipo packs is that if you damage them, they will catch on fire. If you charge them wrong, they will catch on fire. Like charging a 2s pack with 3s setting. or vise versa.. I've owned lipos for 2 years and have not had one explode on me. I take care of the expensive batteries so they last.

I ordered, well sorta!, a CA M15A4 Carbine from Evike.com and it took them 5 days to tell me that it was out of stock and on backorder. So I'm currently trying to get my money back so I can order from airsoftgi. When I get my gun, and a 2s battery pack, I will report back and tell you guys how this battery works and fits in a tight area.

-Tomi

Obsidian
12-24-2005, 03:35 PM
ya Agrovale was going to do the same thing but we have not heard anything. Cant wait to see your results.

AustinWolv
12-24-2005, 05:56 PM
Prior thread here: http://www.lonestarairsoft.com/forums/showthread.php?t=3597&highlight=lithium The small, light aspect sounds great, so be sure to update when you get a chance. The give a great advantage for guns with tight spaces, but otherwise, probably not worth the trouble for a lot of people since they require a different charger.

TomiGun
12-24-2005, 06:16 PM
Chargers are around $40 and up. I'm using a Duratrax Ice Charger ($120) that charges lithium Ion and Polymer, Nimh, Nicads. All digital so you can do cycling to condition your battery. Another good charger is the Great Planes Triton Charger. Does the same but also charges Lead Acid batteries.

Digital chargers are good becaues they tell you how many mAh's your battery is holding.

But anyway,, I forgot to add that these Lithium batteries low voltage discharge is at 3v per cell. So bascially u'r gonna have to put a lipo saftey guard between the battery and the fuse. This will help the battery from discharging lower than 3v per cell.

You can also you 3S packs which are 12.6v But you're gonna have to customize a regulater to feed 7.4-9.6v of power.

Another idea is if you want MORE duration, you can do 2s2p. 2P = Parallel. meaning, a 2100 mah 2s pack in Parellel configuration will put out 4200mah of power. Yet you can still fit the battery in the gun.

If you use thick heatshrink over the lipo packs you should be fine without worrying about the batteries being punctured. I've crashed my R/C planes plenty of times with these batteries being ejected and still using them. NO dents..

The motor is what pulls the power, so it does not matter if you get a HIGH output battery pack. It'll actually be better if you do so that you can alot more duration. Same goes for round cells but can you fit it in your gun?

I'm not a big fan of Tamiya connectors, so I'll be using my RC plane connectors which is rigged on my charger to charge the batteries with.

I actually don't really know if I'm going to be getting the lipo pack for the airsoft gun. I'm new to the game and still need more equipment for playing. I'll be playing at the Texas Ops game in Austin. Maybe if I do get the lipo by then, I can show how it works to everyone at the field.

-Tomi

AustinWolv
12-24-2005, 07:22 PM
Yeah, several of us use Tritons as well. Great little charger for the money since it can handle anything. On the whole though, lots of players have cheaper chargers however that don't support LiPo. That was the point. Tamiya connectors aren't the best, for sure. Players have commonly switched to Dean's. One issue with that though is if your gun is wired for Dean's and your batteries somehow die.......you better hope you can borrow a pack from someone that has Dean's also, or you end up sitting in the parking lot waiting for a pack to charge. While an obvious answer is to always have backup packs charged or an adapter, it is worth mentioning considering the number of times I've seen players have to sit out or borrow guns because of that exact problem.

TomiGun
12-26-2005, 02:59 AM
I totally understand the battery connectors situations. I'm the kind of person who will have more than 2-3 packs. It seems that alot of people spend their money on accessories and such, than spending money on something that they really need.

Anyway, this is going to be a very neat project.

I've talked to a very good friend of mine. He's really into electronics. We are going to come up with a autocutoff for Lipo packs. Since we are going to be using 2S Lipos, 8.4v, we are going to make a autocutoff that will cut the power to the gun at 6v. Once the battery discharges near 6v, the cutoff will shutdown the battery connections. Or we can do a LED light which tells the player that the battery is getting near 6v and is ready to be changed.

The autocutoff will be somewhere near .75"x.75"x.5" inches. Very small. It will have thick wires so to handle the amperage. So till then, this is the only information I can come up with.

As for 3S setup with a regulator to regulate the voltage down to 9v, that is out of the question. Because I do no know how much amps these brushed motors are pulling. If the motors pull too many amps, it will cost alot just to make a regulator for 3s setup. So 2s will be adequate..

Keep in mind, I'm doing this for the guys who have small space for batteries and who would like to try out Lipos.

I will let you guys know what I will do and the progress. This might take a bit. We're going to do some amp testing on the motors to get the EXACT amperage the motor is pulling. We'll be testing this on a CA M4A1 Carbine.

Happy Holidays!

-Tomi