If you're like me and you own a Surface Pro 3, and have had it about a year, chances are that you're just now or already have experienced the AAAA battery the stylus requires is dying.

AAAA batteries aren't exactly common in the US at least where I live, and aren't cheap either. Easily costing 240% more than their AAA counterpart, which also packs double the energy of a AAAA. So closer to 500% more in cost.

AAAA (US$0.005/mAh)
AAA (US$0.001/mAh)

I can purchase a 9V alkaline battery and extract 6 AAAA batteries from the 9V at (US$0.001/mAh)

Here's what happens when you carefully open a 9V alkaline battery pack.

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Careful though, cheaper 9V batteries use Carbon-Zinc instead of alkaline cells.

If you open a 9V and find this: you're out of luck.

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(Dispose of properly, in the EU its illegal to throw out Carbon-Zinc batteries in the trash, in California all batteries are illegal to throw out in the thrash)