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Lithium-Polymer (LiPo) Battery Primer

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Hawaiian,

That 3S battery you linked to must be a relatively new addition as I'm sure they didn't have it when I bought my 168mm 3S's. If they had them I would have bought them as it would have allowed me to fully collapse the stock in the same manner as the 2S packs I am now using.

 

Tom.

 

I am not sure how new they are, I ordered mine maybe 4-5 months ago or so.  They are quite "fat" and take up most of the space in the buffer tube. If running a mosfet, I would probably go with the ones you linked. They are a bit thinner and would allow more space for wiring and the mosfet itself in the tube. 

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Yeah, it was PAS. I'd rather not have to shell out the dosh on both a 'fet and the necessary labour, although it'd keep the warrany in place, no doubt.

 

If 35C seems to not cause overspin, then I may just go and get that 3300 mAh one, as it also appears to be 35C as well. I wasnt gonna touch an 11.1, and 9.6 I know were problematic since my A2 carbine was also a bit funny about them.

 

Thanks, you've been helpful.

All the gen 3 guns now have a MOSFET fitted as standard . I have a feeling it was done to cure the overspin on the gen 2 versions .

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All the gen 3 guns now have a MOSFET fitted as standard . I have a feeling it was done to cure the overspin on the gen 2 versions .

 

Yeah, they mentioned this on their Facebook page, and I can certainly agree this was the case. Ironically, I received the rifle on the same day they announced they were stocking the Gen 3 guns. A little gutted, but I saved a lot of dosh on an otherwise perfectly good rifle as they were reduced in price.

I also have an TR16 A2 carbine which has an erratic semi-auto mode on a 9.6V, but runs just fine on an 8.4V and 7.4V LiPo.

 

Unfortunately, airsoft electronics have always baffled me, down to the wiring. I may get a fet installed in my M16 as I'd like the features and working three round burst, but it'd have to be through PAS, and I somehow doubt that plug and play mosfets like the Burst Wizard work very well, but that's my completely unsubstantiated hunch.

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The plug and play MOSFET will solve the cycling problem on semi but it Dosnt do anything to protect the trigger contacts , may give enough resistance to sort auto as well , also you are adding more resistance to the circuit by adding 2 more connectors in to the equation . Not so bad with deans versions , but very pronounced on a Tamiya connector version .

An airfet MOSFET is only 10 poundish and if you find one yourself pas would fit it for you . Saving you money .as far I I know the factory fit mosfets are not active breaking type , so an airfet would be a higher quality aftermarket version of what is fitted to the gen 3 guns ..

An ab MOSFET is not really needed on a high torque motor so would work perfectly . Jus a case of splicing it into the existing wiring . So would not cost a lot to do ...

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Based on the discussion I've seen and had with PAS staff, the Gen 3 fets should also have AB by default (or at least so they claim).

 

I do agree that adding yet more connectors will increase resistance so a plug n play is not  the best choice for me. I will look into a good mosfet they could fit onto for me, resolving any overcycle issues once and for all, and probably get better performance to boot, particularly if this battery I've ordered still causes overspin. Plus I want 3-round burst because, hey, it's an M16A4.

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I recently bought this battery, to use it in my soon to arrive PDR-C.

 

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=35805

 

It's a 7.4V 1000mAh bat, rated at 20C constant, but I didnt pay attention to the wires and connector, as I was getting a lot more batteries for my planes and cars.

Now that I have it in my hands, I see that the wires are just super thin: 20 AWG, while regular small type batteries for airsoft normally use 16 gauge.

 

The rubber tubing still says 200º C, but Im afraid these will burn up if I use it in an AEG. I dont even know how to put small tamiya connectors on, since the wires seems to thin to grab it.

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just a quick not anyone looking for airsoft batteries in the UK head over to www.componentshop.co.uk great site and really good prices (I am not associated with this company before anyone asks)

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for buffer tube batteries they are ok as long as you don't have a problem, then good luck getting any communication going.

For all other batteries I always use Turnigy Nano packs from Hobbyking as they are silly cheap.

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Got a really strange problem with a lipo battery that I've got, a 2 leaf 7.4v at 1100 mah 15c, when I charge them, the voltage indicates over 4v each cell, so they're pretty much full of juice, yet when I use it on a gun, it behaves as if it's running really low on power, to a point where most semi-auto would lock, full auto's rof sounds ridiculous, and I can confirm the problem isn't with the gun as every other battery tested with the same gun was fine (even with battery with lower voltage displayed in charger).. anyone? 

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Both cells seemed to have exactly the same voltage, don't see how it could cause problems.. I mean I'm not that bothered, I'll just drain it and bin it, but I'm just really curious why that is, since the voltage is showing that it's healthy, it charges okay and balances okay... ummm.. weird. 

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You need to test the ampage output on it to determine what is wrong . Old battery's can still charge up and show the correct voltage . Its when a current drain is put on them that cell damage/ ageing shows itself .. Voltage is only half the equation when it comes down to healthy battery cells . Leaving lipos for long periods of time fully charged can oxidise the cells and cause the type of behaviour you are getting .as can leaving them near a heat source or freezing cold .

Before writing it off run the cells down and do a full balance charge on the battery . If no joy dustbin time for it. ..

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just as a heads up, Turnigy has released a new Lipo the BOLT LI-HV (last bit isn't chem...)

http://www.hobbyking.com/hobbyking/store/__51507__Turnigy_Bolt_2400mAh_2S_7_6V_65_130C_High_Voltage_Lipoly_Pack.html

 

Available from 2S up to 6S, 2400mAh to 5400mAh all at 65C Constant and 130C Burst. Charge C rating is only 2 but at the smallest capacity pack that is still just shy of 5A so hardly bad. The clincher? The cells can be charged to a max of 4.35V compared to the 4.2V of other LiPOs

 

Size looks to be ait of a issue though, the 7.6v pack probably won't fit into many guns hand guard.

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True these are way too large for most any airsoft application. But frankly, 65C is overkill for airsoft anyway. I saw ROF gains going up to higher output batteries from NiMH ones but I doubt you'd see any measurable difference with these, given current affordable battery tech is 20-45C already. The bolt ones are really expensive too - they will be great for RC cars & helis, and 3D planes though.

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£12 for a 2400mAh 65C is expensive? That is cheaper than your average firefox lipo and they are pretty naff.

With time perhaps these will get smaller but I agree, these are pretty OTT for airsoft

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They want $32US for that out of the North American and Global warehouses so you're getting a bit better deal, but compare that against the airsoft ones we're using now which are < $10 or even the 25C 2200's which are $8 and I think I'll still only consider these for high-current stuff!

 

Edit: oops the 25C 2200's are up to $10 now not $8 but stil.... the bolts are 3x the price

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