Loading battery during a trip

[Yvon1]

Hello,

I am planning a hike in the Chinese countryside without electricity. This trip will last nine days.
I have a tablet xperia Z2 and I use it to back up my photos.
Nine days is a long time and autonomy of the tablet will not be enough to cover this entire period. My question:
Is there an external battery that I could connect to the tablet and that either could recharge it or could replace it?

Thanks for your help

[Uliwooly]

There are myriad options online,I use a external battery with solar panels, they are cheap and can recharge your tablet in 3 or 4 hours