What tool is often used to test the health of a battery?

A battery load tester is specifically designed to evaluate the performance and health of a battery under load conditions. When testing a battery, it's crucial to assess not just its voltage at rest, but how well it can perform when required to deliver power. The load tester applies a controlled load to the battery and measures its ability to maintain voltage while under stress. This simulates real-world conditions where the battery must provide enough current to start an engine or power electrical systems.

In contrast, a multimeter can measure the voltage of a battery, but it does not apply a load to gauge its performance under actual operating conditions. A hydraulic lift is unrelated to battery testing, focusing instead on lifting heavy loads. An ammeter measures the current flowing in a circuit but does not assess the battery's voltage under load either. Therefore, the battery load tester is the most suitable and effective tool for determining a battery's health and ensuring its reliability.