Hello! I wanna change this tiny battery in Eachine ev800d to something normal. Could you tell me which option will keep goggles longer enable? 
1. Basket with Li-Ion batteries 18650 3400mAh on head strap 
2. Make XT60 input, and connect it with long cable to lipo 2s 3000mAh in pocket 

I know that many of you make such modifications, can you boast about the battery time of the goggles? 

I am leaning towards the first option, but I heard that the ev800d have a worse range as the voltage drops below 7.5-7.6V. From what I can see, the Li-Ion operates at a slightly lower voltage than stock lipo in this goggles, so I am afraid that I will not lose range and efficiency.