Learning Center

Understand the cell before trusting the number.

BatteryRealData is not only a chart database. This section explains the terms behind the curves in plain language: mAh, Wh, CDR, temp-cut current, pulse current, voltage sag, heat soak, and datasheet claims.

Cell manufacturers Scoring methodology Builder tools
Battery test bench with live data on screen
Real curvesDatasheet checksSimple to follow

Start here

Battery terms explained visually

Each topic is written so a new builder can understand the idea before diving into the chart.

Capacity is the fuel tank mAh is how much charge the cell delivered. Wh is the energy after voltage is included. Bigger is useful only if the cell can deliver it safely.
Voltage sag is the cell bending under load When current rises, voltage drops. A strong high-power cell holds voltage better at the same current.
Heat shows stress Temperature rise, stop temperature, and heat-soak peak help show whether a cell is working comfortably or being pushed too hard.
Current ratings are not all the same Continuous current, temperature-cut current, and pulse current must never be mixed. BatteryRealData labels them separately.

BRD A-to-Z

Quick glossary

CDR / Continuous maxNormal datasheet discharge current without depending on a temperature cutoff.
Temp-cut maxA higher current allowed only until the cell reaches the datasheet temperature limit.
Pulse maxShort burst current. The pulse duration matters, so BRD shows seconds when known.
Usable capacityCapacity above the selected voltage cutoff, commonly 3.0V for normalized comparisons.
Heat soakTemperature that keeps rising after the load stops and before cooling starts.
Internal resistanceResistance inside the cell that causes voltage drop and heat under current.

How to use the site

A simple reading order

  1. Choose the job first.
    Low-power flashlight, high-current tool, pack builder, or stress comparison.
  2. Check the datasheet rating.
    Look at continuous max, temp-cut max, pulse max, temperature limits, charge voltage, and cutoff voltage.
  3. Compare at fair current levels.
    Judge normal BRD score at or below the datasheet continuous rating. Above-limit tests belong in Hero context.
  4. Watch voltage and heat together.
    A cell with good capacity but heavy sag or heat may not be the best cell for high power.
  5. Read BRD Notes.
    Notes explain datasheet conflicts, oversize fit warnings, test context, and honest observations.