The outcome depends on the type of voltmeter used:
- Analogue metre (stylus type): Because this type of voltmeter can only register higher amounts of voltage, measuring coin batteries may be inaccurate.
- Digital metre (numeric display type): these can register lower currents, making measuring a coin battery more accurate. However, it does not always indicate the battery's exact remaining life.
Use a voltmeter that corresponds to the battery type for an accurate result. For alkaline button batteries, use a metre with an input resistance greater than 1 megohm. For lithium batteries, use 10 megohm or higher.