Technical Question

Need a little help here
Thinking of this combination but little worried about its compatibility

www.dx.com/p/4-x-cree-xm-l-t6-2800lm-4-mode-white-bicycle-headlamp-grey-187987
and

www.ebay.co.uk/itm/8000-8800mAh-3-7V-Battery-Pack-Fit-XML-T6-LED-P7-Head-Lamp-Bike-Lamp-/251191159595?_trksid=p5197.m1992&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D14%26meid%3D5588162923237193371%26pid%3D100015%26prg%3D1006%26rk%3D1%26sd%3D251191159595%26

The Battery pack is very high at 8000 mAh. will the light cope??

Thanks

Seems to me that the battery is 3.7V and the lamp needs higher voltage 5.5V and up…

No, the light needs 2sXp (i.e. 2 batteries in series, any number in parallel), but the battery pack is 1s4p (i.e. 4 batteries in parallel).

Could anyone reccommend the longest run battery pack for this light if this pack is not compatible

I believe the 4x26650 battery packs have the most capacity. At least it seems to be more than my 6x18650 battery pack.

These threads have people that have used both and tell where to buy them. If you're only looking for information about alternative battery packs, you're probably best off from starting at the end of the thread and moving towards the beginning.

Thanks for all your replies. I have been wading through all your links leaftye. This should keep me busy for a while
Anymore experiences with the best battery for this bike light then much appreciated