The KVR-208 Microcomputer Battery Internal Resistance Tester is a high-precision internal resistance meter for 18650 batteries. It is produced by Shenzhen Hongda. Generally speaking, the smaller the resistance value, the better the battery's performance. Scope of Application
; Lead-acid batteries and maintenance-free batteries;
, hereinafter referred to as the instrument. The Hongda Battery Internal Resistance Tester applies a 1KHz AC signal to the object under test and obtains its internal resistance by measuring the AC voltage drop. (It differs from the principle of measuring resistance with a multimeter; the value it measures is in milliohms, while a multimeter measures in ohms. Additionally, a multimeter can only measure the resistance of non-powered objects, whereas the internal resistance tester can measure both non-powered and powered objects. Therefore, the two should not be equated.) The internal resistance value is used to determine the degradation state of the battery. (Generally speaking) the smaller the resistance value, the better the battery's performance. Thus, using internal resistance to measure batteries is a fast and highly reliable method.

4. Scope of Application
1. Nickel-cadmium, nickel-metal hydride batteries (packs), and lithium batteries used in mobile phones;
2. Lead-acid batteries and maintenance-free batteries;
3.  Also suitable for research institutions and manufacturers involved in battery research and testing.
4. Can simultaneously display the internal resistance and voltage parameters of the tested object digitally.