Using a Li-Poly battery in a CA 249

[deathbydanish]

I was thinking about purchasing an 11.1V 5300mAh Li-Po pack for use in my CA 249. However, after Balkan Hammer II, I've come up with a few concerns, chief among them is how near freezing temperatures will affect a Li-Po battery pack. I used a pair of 8.4v 4500mAH battery packs over the two days of fighting. My first pack seemed ok for most of Saturday, then towards the afternoon it started to sputter, like it was running dry. However, when I returned to the barracks and charged it up, I had only used up maybe 1000-1500mAh.

My other concern is from when I first bought the CA 249, I was told back then (in 2006) that I should only use 8.4v battery packs, since a 9.6v battery pack would pretty much cause my gears to shred. Is this still the case today, or would I be able to mitigate this by using newer gearsets in tandem with a MOSFET?

[Ganef]

The li-po batts that I was using were behaving the same as any other under the cold conditions. I had the ASOV defroster warming all the squads guns in between fighting.

I don't know about the rate of fire issue.

[Altered_Soul]

Ed,

You should be fine with a 7.2V Lipo, they typically have a much higher discharge rate per the standard Lipo effect and can easily operate most springs like a 9.6v batt.

Lipos are also pretty resistant to the cold, not perfectly, but slightly better than NiMHs (which are better than NiCDs).  Like any battery, keep it close to your chest when playing, or use handwarmers to keep it in peak performance.

[deathbydanish]

One thing I've always wondered about though, was what if I had just finished charging the battery right before we deployed? I know the battery temperature goes up when charging and I do notice that the battery seems to have better response if it was freshly charged. Would that have helped us at all in the cold temperatures?

I'm thinking about getting an Evolution MOSFET then pairing it with a Li-Po battery, maybe a 7.4v in whatever the highest capacity I can find. Then I was thinking about getting whatever the most durable torque up gears are and pairing it with an M120 spring and a Systema Magnum.

[Altered_Soul]

One thing I've always wondered about though, was what if I had just finished charging the battery right before we deployed? I know the battery temperature goes up when charging and I do notice that the battery seems to have better response if it was freshly charged. Would that have helped us at all in the cold temperatures?

Yeah, it is pretty much as straightforward as it sounds.  The only problem is that charging that morning would require some pretty deft timing on the person charging their batteries part.  That can get iffy, I always try to be as prepared as possible before heading out. The only thing that doesn't get done til right before deployment is filling gas in anything that needs it.  

I'm thinking about getting an Evolution MOSFET then pairing it with a Li-Po battery, maybe a 7.4v in whatever the highest capacity I can find. Then I was thinking about getting whatever the most durable torque up gears are and pairing it with an M120 spring and a Systema Magnum.

Oh shi... dude you better be going Red 2 for whenever the next Combat Challenge is. Before upgrading to such a high ROF, make sure to check your boxes can keep up with the rate, as I have been witness to some crazy ROF (mostly 11.1V LiPos though) that shoot way too fast for the feed rate of their magazines.  Especially pressure (read: not spring) fed magazines.

[deathbydanish]

I am resolving to not go Rambo with the SAW. While it is scary to be on the receiving end of a 100 round burst, it is not tactically the most sound thing to do, especially if I have to keep reloading the damn box mags.

[Altered_Soul]

I am resolving to not go Rambo with the SAW. While it is scary to be on the receiving end of a 100 round burst, it is not tactically the most sound thing to do, especially if I have to keep reloading the damn box mags.

No man, I mean, even a 1 sec burst on a 11.1v is pretty fucked up.  7.2v is more than enough for most airsofting needs.

[sargentwolf]

if you do decide to do a li-poly, might wanna concider geting one of these:

http://www.redwolfairsoft.com/redwolf/a ... odID=22687

basically, it slows down your tappet release point, as well as starting the draw-back of the tappet plate a fraction of a second early, their by giving your magazine time to load the next round. a few people have em here, and they work great. i dont know if it would fit on a ca saw gearbox, but redwolf claims it fits on everything but the psg-1 and uzi.

[Firebert]

When your looking at Lipo's bigger isn't always better.  You need to look at the mAh and the C rating.  Any battery that can do about 25-30amp is fine, more than that is just extra and $$.  The easiest way to look at it is and Ill use my 11.1v 5000mAh, 12c battery as an example.  You / the mAh by 1000 and * the C rating, so its 5000/1000=5*12=60amp.  Basically this battery is way more than Ill ever need or use.  So if you decide to look for even a 7.4v lipo you don't need the biggest and most expensive.  If you want a larger mAh batter you can get a lower C rating or vs. versa a lower mAh and higher C rating to get the amp you want.  I found some really nice and small 7.4v, 800mAh, 25C lipo's for under $20 that I really like and you can run them in parallel to extend the run time.

I do not yet know about how the cold will effect it.  I have only had a heat issue once and that was in the middle of the summer towards the end of a day of playing here in AZ.  I also haven't totally ruled out the dirty gearbox possibility.  Since then I had the idea of just keeping them in my cooler in ziploc bags.

[Altered_Soul]

When your looking at Lipo's bigger isn't always better.  You need to look at the mAh and the C rating.  Any battery that can do about 25-30amp is fine, more than that is just extra and $$.  The easiest way to look at it is and Ill use my 11.1v 5000mAh, 12c battery as an example.  You / the mAh by 1000 and * the C rating, so its 5000/1000=5*12=60amp.  Basically this battery is way more than Ill ever need or use.  So if you decide to look for even a 7.4v lipo you don't need the biggest and most expensive.  If you want a larger mAh batter you can get a lower C rating or vs. versa a lower mAh and higher C rating to get the amp you want.  I found some really nice and small 7.4v, 800mAh, 25C lipo's for under $20 that I really like and you can run them in parallel to extend the run time.

I do not yet know about how the cold will effect it.  I have only had a heat issue once and that was in the middle of the summer towards the end of a day of playing here in AZ.  I also haven't totally ruled out the dirty gearbox possibility.  Since then I had the idea of just keeping them in my cooler in ziploc bags.

What the hell is a "C" rating?

[Firebert]

What the hell is a "C" rating?

The C rating is an imaginary figure that they started putting on LiPo batteries to figure out the amount of amps it can safely handle.  In theory all batteries have a C rating but they don't tell you what it is for NiCd or NiMh batteries but its generally 10c or lower which is why you need a 3300 or 3600mHa battery to get better performance from your airsoft gun.  Lipo batteries have a much higher C rating in a smaller package and can handle more amps than the other two.

[Altered_Soul]

What the hell is a "C" rating?

The C rating is an imaginary figure that they started putting on LiPo batteries to figure out the amount of amps it can safely handle.  In theory all batteries have a C rating but they don't tell you what it is for NiCd or NiMh batteries but its generally 10c or lower which is why you need a 3300 or 3600mHa battery to get better performance from your airsoft gun.  Lipo batteries have a much higher C rating in a smaller package and can handle more amps than the other two.

Usually, thats called the "amperage rating", and is represented by IC, or "Amperage Capacity".  There are a lot of different things that C could be from your description, either Amperage Capacity, which means the maximum current in amps that the battery can sustain before taking physical damage, or nominal capacity (normally IsubN), of which the product in question is the current that it should be delivering/capable of handling during normal operating procedures.  

Just wanted to clarify, there are big difference between those two above, which from the description you gave, "C" could mean.  C isn't used in any standard I use.  Doesn't mean it doesn't exist, since product producers don't need to use a standard.  Also, a battery is read in discharge rate, not how much the battery can handle.  I assume thats what C means, its discharge rate (ideal for airsoft, from my experience, is around 25A discharge rate, or 25C according to the symbol you brought up).  

Again, I am also looking at this from a different field of power, so, well, anything goes with the amount of symbols out there in power engineering alone...

[Flak]

If you're worried about the durability of the gun while running a Li-Po, I've seen a CA style gearbox with a Li-Po battery and some super high torque gears. While it will cut down on the possible rate of fire, you'll have much less of a chance to strip a gear or something else.

[KOBO]

At LC I shoved a 11 whatever lipo in my SAW. Yes there was an increase in rate of fire, but it was not that bad. I didn't have any problems, but that was one weekend. Moving parts will wear, more cycles just means wears faster.

[Firebert]

What the hell is a "C" rating?

The C rating is an imaginary figure that they started putting on LiPo batteries to figure out the amount of amps it can safely handle.  In theory all batteries have a C rating but they don't tell you what it is for NiCd or NiMh batteries but its generally 10c or lower which is why you need a 3300 or 3600mHa battery to get better performance from your airsoft gun.  Lipo batteries have a much higher C rating in a smaller package and can handle more amps than the other two.

Usually, thats called the "amperage rating", and is represented by IC, or "Amperage Capacity".  There are a lot of different things that C could be from your description, either Amperage Capacity, which means the maximum current in amps that the battery can sustain before taking physical damage, or nominal capacity (normally IsubN), of which the product in question is the current that it should be delivering/capable of handling during normal operating procedures.  

Just wanted to clarify, there are big difference between those two above, which from the description you gave, "C" could mean.  C isn't used in any standard I use.  Doesn't mean it doesn't exist, since product producers don't need to use a standard.  Also, a battery is read in discharge rate, not how much the battery can handle.  I assume thats what C means, its discharge rate (ideal for airsoft, from my experience, is around 25A discharge rate, or 25C according to the symbol you brought up).  

Again, I am also looking at this from a different field of power, so, well, anything goes with the amount of symbols out there in power engineering alone...

This isn't Rocket Science and you don't need to make it more complicated than it is.  I simply gave you the formula on how to figure out what the amp discharge rate was.  Ok, my fault as I didn't use that exact wording.  You would have to look up more on what the technical/official electrical terms are supposed to be.  However, perhaps I was not as clear as I thought I was.  The C rating itself is NOT the amp discharge rate even though the higher the C the higher the discharge.  If you use the equation I gave you before up there that gives you the discharge amp's.  The voltage its actually not important.  You take the mAh and / 1000 and * C gives you the amp discharge rate.

If you want to read it somewhere else here.  This is one of the manufactures I have used before.
http://www.commonsenserc.com/page.php?p ... ained.html