You can charge the Yeti Tank Expansion Battery in two ways via a Yeti Link Expansion Module. This is possible via: A Yeti 1000 Lithium or larger. An external charge controller.
How long does a yeti battery last?
Yeti Lithium batteries are rated for 500 cycles to 80% capacity. This means after 500 full life cycles from 100%-0% you will still have 80% of the original rated capacity. We expect well over 2000 life cycles on the unit.
Should I keep my goal Zero Yeti plugged in?
Leaving the Yeti plugged in should not hurt the battery. ... Goal Zero actually recommends if possible the generator be left plugged in to maintain the battery. If the generator must be unplugged they suggest it is plugged in every couple of months to recharge fully.