Hi guys ! 
Small & quick presentation of a super handy accessory for long ... very long ... FPV sessions. 
The housing Fatshark to put 18650 batteries high capacity.
unboxing
He squeezed quickly made ...
The box in which the battery is received.

Inside we find the battery only, no explanatory manual.

Grip .. literally!

Overview
View of the box with its connection to food safety goggles / mask. 
I tested it successfully on Fatshark / Skyzone / Eachine goggle one + two. 
It is equipped with a socket type balancing JST-XH 2S which provides power to a potential fan (eg that of Fatshark). 
The size of the cable between the box and the balancing socket is + -38mm while the cable from the box to the main power connector is 60mm

An accessible door on the other side will place 2 batteries of 18650 inside. 
Springs to allow pressure to give good food contact equipment.

Note that the closing of the door is a little difficult with the batteries inside. 
Press firmly to close the door and lock yourself because the small plastic latch with the battery inside it does not lock itself.

Filled with dimensions of 78mm x 19mm x 45mm, we measured 84,5mm x 47mm 23mmx .. this is not quite the same!
  
The weight on sites that offer it for sale to the felt 60g, we measured 40g and 131g vacuum with two 4000mAh 18650 MECO. 
If the weight does not cause any problems, it is significant nonetheless.
 
A bargraph leds, high-tech blue color for viewing the battery status is available on the wafer. 
Pressing the small button (located under my thumb) will activate the time display support.

A little larger and thicker than the original battery of Fatshark, it is not too disturbing the headband but much more convenient than traditional cable, well known SkyZone users, which connects the glasses LiPo in the pocket!

Which batteries put in it?
Personally I put the Li-ion batteries  MECO 18650 4000mAh . 
They have the advantage of being cheap (less than € 7 for 2) are over 500x rechargeable, have a protection in case of overload, can go lower than during discharge LiPo (2.75V) and offer me long hours in operation ... not sure they do exactly 4000mAh (I'd rather order 3000mAh) but it's more than enough to be full! 
Hard to say uptime exactly as I plug in the use and disconnects when I no longer need the equipment ... and also depends on the material (eg, a diversity or a large mask screen consumes more than a receiver only on a small screen).
 
In case of low battery (which has not happened yet), I have Li-ion 2500mAh Trustfire. 
Great brand, great quality too.

To give you an idea in terms of size, this is a 18650 next to a standard 1.2V AA battery

How to recharge?
There are several ways to recharge.
The simplest, I used the charger of my Eachine Goggle TWO . 
This is a charger for Li-ion (because the two goggle use as a base to pack 2 Li-ion 2200mAh), it is available at low cost (7.5 €) and it can charge the pack in a times without removing the battery housing. 
Note that this charger is UK plug, we must add a small adapter UK to EU for use in our decision ... if you often buy in China, you have probably filled lurking ... not sure it comes with!
 
 
another charge solution is to use a charger for Li-ion in which we place the battery for charging. There are all types (with display or as simple as here). 
This requires the batteries out of the case to each recharge which is much more demanding!
 
Comparison of dimensions to get an idea
From left to right, original battery v2 attitude Fatshark, battery Eachine one goggle, goggle battery Eachine two, the case for Fatshark 18650.

A more compact and less expensive alternative
A much cheaper and quite effective solution (but slightly less long autonomy) is not to buy the box + 2 batteries, but use the 18650 battery Eachine Goggle Two  (6.8 €). 
Inside are two 18650 batteries in series, with a capacity of 2200mAh. 
Less bulky than the Fatshark case, a little lighter, but it takes less well on the headband sunglasses ... there is no balancing outlet to power a fan and there are no small monitor to display the power level

Useful links
The Fatshark housing to 18650  in banggood 
the Fatshark housing to 18650 in studiosport
Li-ion Batteries: 
2X Li-ion 4000mAh 18650 MECO
Chargers: 
Charger for Two Eachine Goggle (easiest) - Attention must be a UK / EU adapter 
charger for 18650 batteries (batteries must be removed from case) - Attention must be a UK / EU adapter
Alternative: 
18650 Battery for Goggle Two Eachine

Review by Shunt Belua for Pimousse.be website

Great review! thanks
What sort of run time are you getting with the new pack?

Thx mate, Tests are pending.
With my dom V3 and a rx True d v3 I do only one session of 2 hours with the original one.
Now I guess more
I'll keep u informed, for the moment the weather are too bad

It looks big, I am waiting for furious fpv one too have one fo those and one of these would prettly handy

You now we should put the battery in vertical position at the back so that we coul use on ear headphones

(19-Mar-2017, 11:18 PM)Oscar Wrote: Great review! thanks
What sort of run time are you getting with the new pack?

Hey Mates, 

with one pack it's ok for one day if you disconnect your pack when you don't fly

Cheers

Pim

This could be handy for me. I use 18650s all over the place (vape mods and flashlights mostly) and also I use the Eachine goggles 2 Id have battery options for days lol.
Thanks for the review!

Does it matter if you use flat top vs. button top 18650 batteries? Seems like the extra length would be OK since the springs should give a bit. Any disadvantage to using protected vs unprotected cells? Thanks!

OMG, great review! Thank you for sharing it.

This is all I use anymore. We have a lot of 18650 batteries around our house for flashlights so it made sense. With two 3100mah cells, I can usually record 40 to 50 flights before my Attitude goggles and Pro58 VRX start beeping for low. If I do not record, they would probably last longer. I have flown my 5" with 5 packs, 3" with 7 packs and 2.5" with 9 packs, all recorded and still had 2 bars. Each flight averaging 3 minutes, so about an hour and a half of recording and still had half the charge left.