Mini Internal Resistance Tester [TS457]

Ultra-compact, ultra-budget internal resistance tester / milli-ohm meter (MOM) based on the TS457 modules available on AliExpress. It's primarily intended for finding the internal resistance of batteries (up to 45V), but it works just as well for measuring capacitor ESR and even contact resistance (down to 0.1mΩ / 0.0001Ω). It's small enough to be pocketable, yet since power consumption is so tiny, a single 18650 gives it months of operation on a single charge. All-in, it can be built for under $20, which is very compelling for such a capable, portable tool.

The enclosure provides a space for one 18650 battery and a standard TP4056 charging / protection board, which allows it to charge via USB type-C. On the other side is a slot for a 4-pin JST-XH connector. This is used to connect the Kelvin clamps that are included with most of these kits, and is the same type as is present on the rear TS457 unit. If you don't have a spare, you can always desolder that connector and extend it to the outer case.

Hope you find it useful. Thanks for looking!

Links:

TS457 Module w/ Kelvin Clamps - aliexpress.us/item/3256807448548915.html

TP4056 Charging / Protection Board - aliexpress.us/item/3256805154887650.html

18650 Battery (legit source; choose one from here) - 18650batterystore.com/collections/18650-batteries

Category: Other