Tests and measurements
How a property is measured, and what the numbers mean.
- adiabatic
No heat is allowed in or out, so any temperature rise comes from the sample itself.
- ARC Accelerating rate calorimetry
A test that finds the temperature where a sample starts to heat itself. The sample sits in an insulated chamber, so any extra heat comes from the sample.
- C-rate
How fast a cell is charged or discharged. 1C empties a full cell in one hour, and 10C empties it in six minutes.
- DEMS Differential electrochemical mass spectrometry
Detects gases released from a cell while it charges and discharges.
- DSC Differential scanning calorimetry
Measures how much heat a sample releases or absorbs as it is heated.
- EDS Energy-dispersive X-ray spectroscopy
Shows which elements are present in a sample.
- heat-wait-search
How an ARC test runs: raise the temperature a step, wait, then check whether the sample has started heating itself.
- OCV Open-circuit voltage
The voltage of a cell when nothing is connected to it.
- SEI Solid electrolyte interphase
A thin film that forms on an electrode surface inside a battery.
- SEM Scanning electron microscope
A microscope that images surfaces in fine detail using a beam of electrons.
- SoC State of charge
How full the battery is, as a percentage. 100% is fully charged.
- thermal runaway
A cell heating itself faster and faster until it vents gas or fails.
- XRD X-ray diffraction
Reveals a material's crystal structure by how it scatters X-rays.