Inspect
Battery health
Battery Health charts how a laptop battery's usable capacity changes. A single health reading tells you very little because battery controllers recalibrate and individual measurements drift. A curve over months tells you whether the battery is genuinely degrading and how fast.
The section appears only on devices that report a battery. It requires Novabench Plus and the background service. Novabench builds the chart from logged snapshots rather than a live read.
The header figures
Above the chart, Novabench shows the two numbers it derives the health percentage from:
Figure | Meaning |
|---|---|
Full Charge Capacity | What the battery currently holds when fully charged |
Design Capacity | What it held when new, per the manufacturer |
Health is the first divided by the second. A battery at 4,200 mAh against a 5,000 mAh design capacity is at 84 percent health.
Design capacity is a fixed manufacturer value, so every movement in the health percentage comes from the full charge figure. That figure is the battery controller's own estimate, and controllers revise it after deep discharge cycles. A reading that jumps several points in one day and settles back is recalibration, not damage.
Live grid and history chart
The top of the section is a live sensor grid: current charge, discharge rate, and the other battery sensors described in sensor monitoring.
Below it, the history chart plots capacity and charge level over the selected period. Use the Date Range control in the Display sidebar to switch between Past Day, Past Week, Past Month, Past Year, and All.
Past Month and Past Year are the ranges that answer the replacement question. Past Day is mostly useful for watching a single discharge cycle, for example to see how steeply the battery drains under a particular workload.
Judging degradation
Lithium-ion cells lose capacity with cycles and with time, and the curve is not linear. Most batteries drop quickly over the first hundred cycles, then settle into a slow decline. What you look for on the chart is a change in slope.
Read the chart alongside the Cycles count in the system inventory. A battery at 80 percent health after 800 cycles behaves normally. The same 80 percent after 150 cycles is not, and that is a warranty conversation rather than a replacement purchase. See warranty and coverage for what the device is entitled to.
Confidence matters
When the chart is empty
An empty chart means there are no logged snapshots in the selected range, not that the battery is fine. Sensor logging must be on first.
If the overview's Battery Health preview shows a Configure logging link, logging is off. Turn it on from Settings, as described in sensor monitoring. Data starts accumulating from that point forward. Novabench cannot backfill history it never recorded.
If the section reports that battery status is not available, the device either has no battery or exposes one Novabench cannot read. Some docked and external batteries fall into the second case.
Calibration
If you want a deliberate, controlled measurement rather than a passive trend, run the battery test. It drives a known workload through a full discharge and measures real runtime. Capacity health and real runtime are related but not interchangeable: a healthy battery can still provide poor runtime when a background process consumes excessive power.
If the controller's own readings look wrong, rather than the battery being worn, a calibration cycle can re-anchor them.