Battery Internal Tester Comprehensive testing for lithium batteries: measures internal resistance and capacity, along with voltage, current, and power, enabling accurate assessment of battery health and performance across a wide range of devices. Clear 1.77 inch LCD display: shows internal resistance, capacity, voltage, current, and power simultaneously with clear visuals for quick interpretation and informed decisions, reducing downtime and enhancing reliability. Flexible modes: automatic, charging, and discharging modes provide versatile testing options. After activation, simply select the desired mode for a streamlined and efficient process suitable for both beginners and experienced users. Data management: automatically resets capacity, energy, and time data when powered off or when switching modes, ensuring you always work with current information for reliable test results. Compatibility and practicality: designed for evaluating lithium batteries in various applications, including single cells and battery packs in consumer electronics, power tools, RC models, and other devices. Use scenarios: In a or refurbishing setting, verify remaining capacity and internal resistance of suspect cells before replacement. In development or quality control, cycle through charge and discharge to validate lithium packs and their performance. In the field or at a service site, quickly assess battery readiness of devices to prevent unexpected failures.