Batteries

All that's required is a salt and: battery.

List

• https://www.eevblog.com/forum/projects/coulomb-counter-ic-for-coin-cell-products/ - not many options for measuring current out of a coin cell, without drawing a notable amount of current.

Tips/Techniques

Cell vs. Battery

A bit of semantic nonsense, but technically a battery is made up of cells. https://www.eevblog.com/forum/projects/biggest-battery-capacity-for-22-x-22-mm-case/ - cell vs. battery (cell is a single, battery is a collection of cells)

Counterfeit Capacities Over 3.6mAh

3.5 or 3.6mah is the highest single 18650 cell you can buy. a couple amusing anecdotes.

• https://www.eevblog.com/forum/dodgy-technology/10ah-18650-cells/

NiCads/NiMH

Noise on Older Batteries

• https://www.eevblog.com/forum/metrology/diy-0-1-to-10hz-noise-amplifier/ -Page 3 or 4. nimh or nicads have more voltage noise as they reach EOL