• Nvidia Shield Teardown

    Those are 18650 hi-capacity cells (18650 comes in various capacities depending on manufacturer) off the top of my head i can find a LG Lithium with 2600mAh at ~7$ each WITH tabs(also 2800mAh ultra capacity). Watch out which one you buy as 18650 comes from 1400mAh-ish to whatever they can put with new chemistries...

    So changing the batteries(even putting beefier ones) should not be expensive -problem is resetting the charge controller that looks like a normal pack charger(like from a laptop, i can see the two white leads in the middle, those look like the I2C control lines, you can check it out with a bus pirate for example) thus it will maintain usage and capacity history(changing the cells alone won't be of much use as it will show a deflated battery)