SOPMOD Lipo conversion

[Capitano_Tomtom]

First thing; was unsure as I want advice on lipos, yet it is from a technical aspect so mods feel free to move to Tech help.

Moving on, I've recently become the proud owner of one TM CQBr Recoil. Love it. Completely. 110%.

BUT, the batteries are a massive pain.

Now I've always been a Ni-Mh kid, using a 14 year old Ripmax propeak charger that does the job fine.
However I'm looking at something other than the poor proprietary batteries TM produce. Now I don't wish to front-wire this, so I'm looking at lipos in the stock.

I've had the back quick-change block and fuse off, and so far as I can tell the metal bars that run along the stock terminate behind said block. This should be an easy case of soldering on some deans connectors (have I just got a foul pair or are they ridiculously tough to connect and disconnect?) and running lipos in the tubes.
I've looked at measurements and think you can fit lipo tubes, JUST. But I've never worked with lipos before, so I'm really after advice on chargers and brands, plus ideally if anyone is running lipos with a connector other than the proprietary in a SOPMOD or CQBr.

I know the basics about lipos; i.e. don't overcharge/overdischarge, put in fires, eat, etc. etc. but as this would be a new technology for me I'd like to know how it would apply to my particular rifle.
I know there are Eagle6 packs out there, but I could quite easily knock up a system for far less than they are worth, including a charger.

I wouldn't mind if it was a crane-stock style or two single batteries that i would have to manually change if one ran low, I just don't want to tamper with the gun itself and start pulling bits off.
I understand that HOT POWER lipos have been used in these situations before; does anyone have opinions on these? My local retailer only stocks Kong Power lipos.

Cheers for any help guys, much appreciated.

Tom

[Gaffa]

Re: SOPMOD Lipo conversion

Charger is more important than lipo battery brand itself.

I'd go for a Turnigy Accucel 6 - cracker bit of kit, however you can also get an IMAX B6 (B6DC I think it's called) which has got a built in power supply*. This is the 5A (I think?) adaptor cable that often doesn't come with the lipo charger itself unless otherwise stated.

In terms of charging, it's really simple. Connect power lead > Charger comes on Automatically. From there, its:

Program Select "Lipo Battery" > Press start. If this is not selected when the charger comes on, use press "Stop" and "-" (minus) buttons to cycle through the options.

From here, you choose Lipo Balance, again cycle through if necessary.

Press start once to set the charge current. Now I normally do 50% of the Batteries capacity. So if the capacity is 2000mAh, I would charge at 1.0A (1000mA). If you want to fast charge, charge them at the same rate (2000 = 2.0A) or slow charge for long term protection at 25% (2000 = 0.5A). These are rough figures and I can't guarantee this is correct, but it works for me and I'm coming onto my 3rd year using lipos in Airsoft.

Once you've set this, press start. You'll then see the other option begin to flash.

This is where you'll need to select how many cells the battery has. Typically, you'll be using 7.4v (2 cell) and 11.1v (3 cell) batteries in airsoft. So choose (2 cells = 7.4v lipo, 3 cells = 11.1v lipo, etc). My Turnigy does 7.4v (2S) to 22.2v (6S), others will vary. Select the 7.4v option if it's a 7.4v battery, obviously.

If you haven't already done so, you'll want to connect your battery. You need to connect both the charging plug (Tamiya/ Deans/ XT-60, etc) as well as the Balance plug (small white plug with different coloured wires) to the relevant socket on the charger and then you'll be ready to charge.

HOLD the start button, and the charger should check that the Cell information you entered (2S = 7.4v, 3S = 11.1v) is the same as what the charger reads from the battery. If the data matches, press the start button again to begin charging. If it doesn't, just press the Stop button and re-enter correctly.

---

In terms of batteries, even really cheap China batteries have worked well for me. Albeit, not as good as better brands such as Turnigy (who make batteries also) but for the price (~ £7 for a 1900mAh 20C 7.4v battery) I haven't complained.

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Definitely go for the modification on the SOPMOD. Just solder on the wires as you said, and make sure they're long enough. Can't you buy a Crane Stock lipo and fit the 2 sections down the Stocks battery compartments? That would be better and obviously opens up more options.

[druid799]

Re: SOPMOD Lipo conversion

I've converted my Sopmod to lipo , removed all the quick change gubbins from the stock then from the stock tube , cut the wire just behind the terminal on the stock tube (so I could put it all back if I wanted), soldered a deans to it that had 5inches of wire all ready soldered to it , job done . I can fit a 7.4v 1600 cranestock down the legs no probs . And my sopmods been upped to around 340fps and it runs fine all day on that batt .

[blobface]

Re: SOPMOD Lipo conversion

First thing; was unsure as I want advice on lipos, yet it is from a technical aspect so mods feel free to move to Tech help.

Moving on, I've recently become the proud owner of one TM CQBr Recoil. Love it. Completely. 110%.

I actually have a Marui emod style stock already wired up with a 7.4v 3000mah lipo and gold plated connector bars, don't suppose you'd be interested to buy it off me (with the battery)? The stock itself did cost me a fair bit since mine was originally the crane stock, so I bought it separately, trying to get rid of it for £40, let me know either way.

[Capitano_Tomtom]

Re: SOPMOD Lipo conversion

Cheers for the information guys, real wealth of knowledge on here. Especially from somebody who has not a clue about lipos in action. (never even seen one in real life due to my local stockist being out of stock!)
Druid what lipo have you managed to fit in your stock? I've looked at a variety of crane stocks but have been having to use dimensions off the internet so have been hesitant to buy if it won't fit.

Blobface, is that £40 for the whole lot? If so I may very well take you up on that offer.

[PureSilver]

Re: SOPMOD Lipo conversion

Necropost, I know, but this thread seems like the logical one to reboot since I've got the same questions to ask. My SOPMOD is my only AEG, so I don't own any batteries or a charger. I figured that I might as well get LiPo technology rather than buying into NiMHs and having to upgrade later, so I need recommendations for a battery and for a charger. I've got a totally unmodified SOPMOD, and I'd like to unscrew the quick change stuff and solder on a new connector, and then get a Crane-stock LiPo. So far as I can tell:

1. The standard TM SOPMOD battery is an 8.4v 1300mAh NiMH.
2. An unmodified gun means using a 7.6v LiPo. 11.1v destroys guns that aren't built to cope with the higher voltage.
3. My batteries need to fit inside the original TM SOPMOD stock. LiPos are usually flat, and the tubes in the stock are round and not particularly large.
4. A commonly recommended battery is the 7.4v Hot Power pack, which uses round cells and appears to fit nicely inside the stock. The Hot Power 7.4v is a 3000mAh 15C LiPo pack.
5. My local doesn't stock the Hot Power, but they do stock a 7.4v Vapex pack, which uses flat cells. I'm not sure if it will fit inside the stock. The Vapex 7.4v is a 1450mAh 20C LiPo pack.

Their specs are as follows:

	TM SOPMOD	Hot Power	Vapex
Voltage:	8.4v	7.4v	7.4v
Capacity:	1300mAh	3000mAh	1450mAh
Maximum Current Draw:	11.7-15.6A*	45A	29A

*Judging by other 2/3A 1.2v 1500mAh NiMH cells, the SOPMOD pack probably has a C-rating between 9 and 12, giving it a maximum maximum current draw somewhere in the region of 11.7-15.6A.

By my estimation, then, both the Hot Power and the Vapex exceed the original SOPMOD battery so either should be fine. The Hot Power, with its significantly larger capacity, will presumably last much longer than the Vapex, but the Vapex, being from a much more reputable company (the Hot Power brand doesn't appear to be used on anything else) might be more reliable. A few questions:

1. Does anyone have any experience with either the Hot Power or the Vapex?
2. Does anyone know if Mini-Deans are as good as normal Deans? I'd rather have Mini if it's not a disadvantage, since the space in the rear of the stock is pretty limited.
3. Can anyone recommend a good LiPo charger? I need it to plug into the mains via a standard 3-pin plug.

[sparrowhawk]

Re: SOPMOD Lipo conversion

there is a lipo nunchuck battery that can fit into the original housing of the quick change battery, someone has posted the name,and source of it, but i cant recall where

[PureSilver]

Re: SOPMOD Lipo conversion

That's the Hot Power, I think. Eagle6 just confirmed that the Hot Power's still the battery to get, but it's impossible to get one into the UK before Sunday, so I'm exploring other options.