AA and AAA battery tester

• DISCLAIMER: I DO ELECTRONICS AND 3D DESIGN SOLELY AS A HOBBY. THERE COULD BE ERRORS THAT CAN RESULT IN ALL KINDS OF DAMAGE. USE THESE DESIGNS AT YOUR OWN RISK.
• This design is released under Creative Commons Zero (CC0) license.
• Author:
  • Svjatoslav Agejenko
  • Homepage: https://svjatoslav.eu
  • Email: svjatoslav@svjatoslav.eu
• See also:
  • Other physical projects in this repository
  • Other projects hosted at svjatoslav.eu

Simple rechargeable Ni-MH battery tester. The problem with those batteries is: right after you take them out of charger, voltage level at their terminals is good. But some old batteries will get empty/discharged way too quickly under normal load. This device is intended to discover old batteries with reduced capacity.

Freshly charged batteries are tested under high load by shorting battery + and - terminals using 5 ohm power resistor (R1). Simultaneously battery voltage is being measured while under load.

I use vintage analog voltmeter. Instead of power resistor I use Nichrome resistance wire. It gets hot quickly!

• Body:
• Cover:
• Download:
  • FreeCAD project
  • body STL file
  • cover STL file