Apollo glider resurrected- battery question

Looking to trying a spot of thermal flat field in the summer , possibly entering a comp or two.
I've found a Pete Kessel Apollo glider which has. Multiplex 600 motor. The battery used was a 7 cell ( 2/3 sc )) in line 1200 nicd about 6 inches long.
I was wondering if a 2S lipo would be a suitable battery, when I came across on HK an "airsoft" battery about the same shape which it says is a 2S lipo. Apparently it is used in some sort of gun!
Would this airsoft battery work as an ordinary 2S lipo and would it be suitable for use in the Apollo...?
It is cheap enough to try out, but I didn't want to get something that might be unsafe.

Knowledgeable advice appreciated
Thanks

Hi, Dave.

You should contact Chris Hague about this. He runs the 600RES activities, for which the Apollo was designed. You can reach him on 07967 three oh six 201.

Dave - I have no experience running a Ni-mH ESC from a Lipo but suspect you would need to be able to reconfigure the ESC to recognise Lipo voltages. Otherwise it will not provide electric motor cut to protect the BEC power to your radio.
If you have selected Airsoft batteries because the size suits your model, provides the capacity and discharge rate you need - i see no reason why you could not use them -

Thank you Phil and Kevin.
I spoke to Chris who was helpful. However he hasn't used lipo with that motor.
Further research on the esc shows it cannot be configured for lipo. I'll get a nimh battery and go from there. I may in future change motor, esc and use lipo, if I think it's worth it.
HK seem short on 8.4 nimh batteries , and component shop isn't a lot better, I can get a 1600 but 1200 seem rarer than hens teeth
Anyway, thanks again for your assistance

Do not get a NiMH.

I'm just heading out but will be back in touch later this morning with better advice.

If it were me I'd buy a 2 cell lipo that weighs about the same as the 7 cell NiMH it's replacing. Look at the zippy compact range from Hobbyking.. I'm in my phone now so cannot easily look for you. A 2 cell lipo is going to be as cheap or maybe cheaper than a NIMH. It will also have so much extra capacity that you'll never reach a low voltage cutoff. As such, the existing ESC will be fine.
At a later date you would probably want to replace the heavy and inefficient brushed motor (and controller). This is also a cheap fix.
There is someone in the WSA flying an Apollo but I can't remember who. He would be able to advise on motor and ESC but get yourself up and running with a 2 cell battery first

The latest Apollos use a brushless motor and a motor timer/height limiter,but they do retain the seven cell NiMh battery as part of the competition specification. If you aren't going to fly in competitions, the battery and power train aren't important. Enough power to climb to a decent height with enough left over for an emergency power-up,and enough weight to enable the glider to penetrate and get up-wind, with the C of G in the right place, the Apollo will more or less take care of everything else. Component Shop is a good source of 7 cell NiMh packs.

The following are all available in the UK warehouse. They all weigh approximately the same as a 7-cell 2/3 AA NiMH. They have about 2 to 3 times the capacity of the NiMH. The only reason to use NiMH would be if you intended to compete in Chris Hague's 600RES ... and then you'd have to buy a brushless motor and controller anyway.

hobbyking.com/en_us/zippy-compact-1800mah-2s-25c-lipo-pack.html

hobbyking.com/en_us/zippy-compact-1300mah-2s-25c-lipo-pack.html

hobbyking.com/en_us/zippy-compact-2200mah-2s-25c-lipo-pack.html

hobbyking.com/en_us/zippy-compact-1500mah-2s-40c-lipo-pack.html

Thanks very much Mike and Brian.
I'm not intending to fly in Chris's 600 res. Comps so I'll get the suggested lipo. It will be interesting to see how light I can go re battery in view of Brian's intimation that the battery size is needed to assist penetration . Staying up is also important ( talking about gliders ,dear. ), so maybe the lighter the better.
Must be an optimum somewhere.
Cheers and thanks again

I've been flying Peter Kessell's Apollos since just after he designed and built the first one. We started off with brushed motors and heavy NiMh and have since moved onto much lighter brushless motor and LiPo's.

We have had to lengthen the nose by about 1 1/2" to facilitate the lighter motor and obtain the right cofg without adding lead. I have recently been flying mine on a 2S lipo with Chris's standard brushless motor, but with a 9x6 prop, it climbs very well and with the reduction in weight glides superbly.

Just a shame that Pete isn't around anymore to see how much better they fly now.

If anyone is interested I still have some of Pete's old fuselages and wings for sale at very reasonable prices.