With some of the latest battery models and macOS versions, the manufacturer info may unexpectedly disappear: If you run Battery Monitor with certain combinations of hardware model and operating system, the identification of the battery manufacturer may sometimes disappear from the main window after waking your Mac from sleep mode.
Workaround: This is a known defect of specific macOS versions. The operating system driver communicating with the battery may lose the battery manufacturer entry during the wake procedure and no longer publishes it to user Apps. Restart the computer to resolve this problem. Apple may or may not fix this problem in future versions of macOS.
The health assessment of batteries for Macs with Apple Silicon may be shown as “unknown”: If you are using a portable Mac with Apple M1 processor, the line Assessment in the section Battery Health might sometimes be indicated as being unknown, instead of showing the true value. This effect can vary depending on operating system version.
Workaround: This is a known defect in some versions of macOS. Update the operating system to macOS 11.6 or later to get more reliable results. If this still doesn’t help, restart the computer.