Lithium-Polymer (LiPo) Battery Primer

[Kunlun]

How would someone rate the 9.9V 1000mAh 20C Li-Fe's?

http://www.component-shop.co.uk/html/airsoft_li-fe.html

 

Been running Firefox 11.1V 1200 mAh 20C LiPo's but they need to be replaced soonish.

[hawaiianjuggernaut]

Firefox? Bleahcchchch. Id advise just replacing your firefox ones with some turnigy nanotechs. Best LiPos ive ever got.

[richwuk]

How would someone rate the 9.9V 1000mAh 20C Li-Fe's?

http://www.component-shop.co.uk/html/airsoft_li-fe.html

 

Been running Firefox 11.1V 1200 mAh 20C LiPo's but they need to be replaced soonish.

 

I've been running the 1000mAh & 1600mAh Li-fe batteries since May and they have been brilliant.

 

I've run one dry and kept trying to fire with no damage to the pack (that I can tell). Very consistent until they are discharged, you won't know until the pack is nearly 'dead'! They also keep there charge nicely and I'll charge them up after a game and they keep there charge even after 2 weeks.

 

The downsides I can find are fitment, those 1000mAh packs just fit into an M4 buffer tube (a little tight but nothing major) and discharge rates. When using with a neo magnet motor they both get warm, I know I have gearbox issues but not sure how much of a factor that is (That's with a 1000mAh pack, I've just noticed the 1600mAh have a much better discharge).

[LordElpus]

if they are getting warm then you are pulling more than they are happy with. May not cause any real problems past reducing their lifetime

[Kunlun]

Any shops for lifepo's? 

[LordElpus]

Google. Just don't buy from airsoft shops, get them from R/C Hobby shops.

[Kunlun]

My google-FU is weak today

 

I did find the Flame LifePO4 batteries though and they seem interesting. Would a 9.9V LifePO4 1000mAh 15C be sufficient enough for let's say a Systema PTW where only single shot is being used?

[HeadStAtE!]

Anyone know the best place to buy Lipos and LifePO4 in the UK?

[DrAlexanderTobacco]

www.component-shop.co.uk

 

Nice guys, fast delivery, great prices!

 

(I am in no way associated with them, save for me being a regular customer).

[Shroomalistic]

I just bought 3 of these http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=28640 . still cant believe how small they are.  They should be fine for pulling under 400fps right?  Im just getting back into airsofting again and my old batteries have took a .

 

I dont know if this has been answered yet,  but let say you have a 7.4v 20c 1300mah battery and a 7.4v 35c 1300mah battery,  will the 35c last longer(more shots) then the 20c when put in the same aeg? 

[hawaiianjuggernaut]

they should be good in most guns unless you have a seriously FUBAR gearbox.

 

The 2 batteries have the same capacity (MaH) and voltage, but the 35c will run out faster because the C-rate is the discharge rate. Faster discharge rate=lasting shorter time.

[LordElpus]

The C rating just gives you the amounts of Amps the battery can supply with constant draw and burst draw (over 4s) The one you linked can give 32amps constant 64A burst.

 

For your example (changed the mAh to make maths easy). Battery A - 1200mAh 20C (24A) and battery B - 1200mAh 35C (42A)

 

If your gun needs 20-22A constant (more than 4 second current burst) to run at 100% then there will be no noticeable difference.

 

If you gun needs more then 24A to run at 100% then Battery B will last longer as it has to work less to supply needed current. .

 

I will state that this is how I understand the tech, it may not be 100% accurate and may have math/grammar/spelling issues.

[Shroomalistic]

I was kinda thinking that since they have the same mah same voltage that since the higher c rating battery is using a lower percentage of its running amps,  it should run longer since its not being maxed out nearly as much as the lower c rating battery.

[hawaiianjuggernaut]

well im not an expert on the battery thingy, but thats what ive heard/researched

[jal3]

Think of it as this.

 

Voltage is how fast the motor will run.

Ampere (not Ah, just A) is how much juice the motor needs to pull the load.

 

So a M100 gun on a 12v battery will be driven at 12v and the motor will pull 15A.

And a M120 gun on the same 12v battery will be driven at 12v and the motor will pull 20A.

 

So why does discharge rate matter?

 

Well, batteries are complicated things too. You could even view it as a motor in itself. The more A you try to pull out of a battery (eg. 15A on a M100 spring vs 20A on a M120 spring), the lower the voltage will be out of the battery.

So the battery may hower around 12,6v with no draw on it, but when you pull 15A out of it the voltage from the battery will drop to maybe 11v and when you pull 20A out of it it may drop to 10v.

So the voltage that determines the RPM of the motor drops, and therefor the motor runs slower.

 

The discharge rate tells you how well the battery copes with load. A high discharge battery will keep a higher voltage during load than a weaker discharge battery.

 

Thats why a high discharge battery gives a higher ROF, and why the ROF loss is even bigger at higher springs (because you pull more A).
 

I personally recommend the 11,1v 2200mah 30-40C batteries for everything. Anything more is a waste of money, weight and space.

 

 

 

Also this is correct:

I was kinda thinking that since they have the same mah same voltage that since the higher c rating battery is using a lower percentage of its running amps,  it should run longer since its not being maxed out nearly as much as the lower c rating battery.

[Triggerhappychappy]

they should be good in most guns unless you have a seriously FUBAR gearbox.

 

The 2 batteries have the same capacity (MaH) and voltage, but the 35c will run out faster because the C-rate is the discharge rate. Faster discharge rate=lasting shorter time.

 

The reason why this^ is totally wrong is because a battery that struggles to provide enough current will also droop it's voltage at the same time ( lower firing rate ), and in turn the battery will heat up more ( lower discharge rating is due to higher internal resistance largely ). If the battery is struggling & overheating, that isn't a good thing and is why crappy lipos swell up and hit the Low Voltage Cutoff ( LVC ) level much sooner.

 

Lipos with a higher discharge rating will not run out quicker ( runtime = mah capacity essentially, all things being equal ), rather the opposite, since they can maintain a healthy voltage level for longer due to being able to provide more current without suffering voltage droop & overheating. Whatever research you did, or whom ever you listened to, you either misunderstood or they did...

 

Think of it as this.

 

Voltage is how fast the motor will run.

Ampere (not Ah, just A) is how much juice the motor needs to pull the load.

 

So a M100 gun on a 12v battery will be driven at 12v and the motor will pull 15A.

And a M120 gun on the same 12v battery will be driven at 12v and the motor will pull 20A.

 

So why does discharge rate matter?

 

Well, batteries are complicated things too. You could even view it as a motor in itself. The more A you try to pull out of a battery (eg. 15A on a M100 spring vs 20A on a M120 spring), the lower the voltage will be out of the battery.

So the battery may hower around 12,6v with no draw on it, but when you pull 15A out of it the voltage from the battery will drop to maybe 11v and when you pull 20A out of it it may drop to 10v.

So the voltage that determines the RPM of the motor drops, and therefor the motor runs slower.

 

The discharge rate tells you how well the battery copes with load. A high discharge battery will keep a higher voltage during load than a weaker discharge battery.

 

Thats why a high discharge battery gives a higher ROF, and why the ROF loss is even bigger at higher springs (because you pull more A).

 

I personally recommend the 11,1v 2200mah 30-40C batteries for everything. Anything more is a waste of money, weight and space.

 

 

 

Also this is correct:

 

What he^ said.

[npav85]

If you really dont want as much Volts and amperes, you should look at an 7.2 volt lipo, its about the same as an 8.4 battery except it has a lot more amperes. It gives the gun a realistic RoF though. 

[LordElpus]

7.4v

[Triggerhappychappy]

And they're 8.4v fully charged by the way- 7.4v is just the nominal voltage...

[trdsupragt]

Man what a huge thread. My head is just spinning from the amount of information on here. 

 

I was hoping you guys could help me out with my gun.  I've got a G&P M4 MOE PTS that I bought late last year, and it now has an Infected MOSFET in it. I've been running an 11.1v 15C 900mah lipo in it, but only for target practice every so often, so I can't really report on any performance issues.

 

However, I will start playing again, and would like to purchase more batteries. I thought about purchasing an 11.1V 25C 1000mah lipo, but I'm afraid it might perhaps be too much for the gun? I rarely use the full auto feature, and I hardly even burst at all. So essentially, I just want the quickest trigger response possible without ruining my gun. All my research leads me to believe that a 7.4 would be sufficient, but what's the highest discharge rate I should look at? I'll be fitting the battery in a PEQ-15. 

 

Given that, perhaps my initial choice of the 11.1 25C would be fine, since I've got a MOSFET installed?

[Baddbaz]

Cell quality is also a big issue with lipo batteries . Have lost count of how many fraudently labeled battery's I have come across . Battery's stating 30 /35 c on the labels , when they actually are pushing out 15/20 c . Especialy the cheap lower quality clone battery's

Also storing lipos fully charged for longer periods of time is realy bad for the cells ,

If not in use / storage , they should be left at approx 50% of their charged state , this stops the battery cells oxidising and degenerating . . Never leave them for any length of time in their most discharged state ,as this also causes cell damage

Most decent chargers. Accucel , turnigy , jp pro , fusion , will have a lipo storage charge program built into them . Keep your battery's dry and away from extremes of temperature whilst in storage and ideally in a fireproof bag or tin

Look after your battery's and you will greatly extend their life span

[Apex]

Man what a huge thread. My head is just spinning from the amount of information on here. 

 

I was hoping you guys could help me out with my gun.  I've got a G&P M4 MOE PTS that I bought late last year, and it now has an Infected MOSFET in it. I've been running an 11.1v 15C 900mah lipo in it, but only for target practice every so often, so I can't really report on any performance issues.

 

However, I will start playing again, and would like to purchase more batteries. I thought about purchasing an 11.1V 25C 1000mah lipo, but I'm afraid it might perhaps be too much for the gun? I rarely use the full auto feature, and I hardly even burst at all. So essentially, I just want the quickest trigger response possible without ruining my gun. All my research leads me to believe that a 7.4 would be sufficient, but what's the highest discharge rate I should look at? I'll be fitting the battery in a PEQ-15. 

 

Given that, perhaps my initial choice of the 11.1 25C would be fine, since I've got a MOSFET installed?

 

 

You have been running it on a 11.1v for all this time; it will be fine on a 11.1 with a better C rating [you should be able to get a 2200/2600mAh battery in that handguard i think]

[sigma3]

I've got a new lipo battery that will not charge.  Every time I try it on my charger (a B6) it reads "Over Voltage."  Does this mean the battery has been blown?  Or what?  It's a simple 1800 Mah 7.4v; I've never seen this problem before but I DID loan this battery out and it's possible the guy I loaned it to drained it completely, because he's not used to lipos.

[Baddbaz]

Try balancing it . May not work , but definatly worth a try ..

[infected]

I've got a new lipo battery that will not charge.  Every time I try it on my charger (a B6) it reads "Over Voltage."  Does this mean the battery has been blown?  Or what?  It's a simple 1800 Mah 7.4v; I've never seen this problem before but I DID loan this battery out and it's possible the guy I loaned it to drained it completely, because he's not used to lipos.

 

Before you do anything, check the voltage of each cell. You might have a cell that is overcharged if your friend used the wrong type of charger. No cell should be over 4.2v.

 

If one is too high try to just balance the cells (do not charge them).