and Jargon

Abbreviations and Jargon in the battery world.

4R’s – this is battery pack Repair, Remanufacture, Repurpose and finally Recycle.

AC – Alternating Current

ACIR – Alternating Current Internal Resistance is normally the impedance of the cell at 1kHz.

Ah – Ampere hour is an alternative unit of electrical charge. Product of the current strength (measured in amperes) and the duration (in hours) of the current. The quantity of electricity (capacity) of a battery or cell is usually expressed in ampere hours. Unit of battery capacity.

Anode Free – a battery cell where the Anode is formed during the cell formation cycles.

BaaS – Battery as a Service is the name for swappable battery packs. Designing swappable batteries: Swappable batteries inherit outer design, power output and data exchange protocols of their precursors.

BMS – the Battery Management System is the control system that manages and reports out the status of the battery.

BoL – Beginning of Life

C2P – Cell to Pack design that removes the need for physical module parts.

CC – Constant Current

CC-CV – Constant Current-Constant Voltage

CEI – Cathode–Electrolyte Interphase doesn’t exist during normal cycling of a cell, however, it appears during short circuits and when operating a cell at higher voltages.

CID – a Current Interrupt Device is a pressure operated device used to disconnect a cell from the circuit if it fails in some way.

C-rate – a measure of the rate at which a battery is charged or discharged relative to its capacity. It is the charge or discharge current in Amps divided by the cell capacity in Ampere-hours. A 1C rate means that the discharge current will discharge the entire battery in 1 hour.

CSC – Cell Sensor Circuit that brings voltage sensing, temperature sensing and balancing together for a sub-grouping of cells. This then communicates with the BMS master board.

DC – Direct Current

DCIRDirect Current Internal Resistance is normally measured by applying a current pulse to the cell and measuring the voltage response of the cell.

DoD – Depth of Discharge

DUT – Device Under Test

EIS – Electrochemical Impedance Spectroscopy offers a non-destructive route to in-situ analysis of the dynamic processes occurring inside a battery by measuring the complex impedance.

EoL – End of Life

FC – Fast Charging is all about rapidly charging the cell or battery pack in a very short time. Normally this would not take the cell to fully charged as it is all about getting a usable amount of energy into the battery in the shortest time.

HPPC – Hybrid Pulse Power Characterisation

HV – High Voltage battery pack. “High Voltage” means the classification of an electric component or circuit, if its working voltage is > 60 V and ≤ 1500 V DC or > 30 V and ≤ 1000 V AC root mean square (rms).

ICA – Incremental Capacity Analysis is an analysis method used to investigate the state of health. It is based on the differentiation of the battery capacity over the battery voltage. Can be used for a full or a partial cycle.

kWh – kilo Watt hour is 1000 Watt hours and is a unit of energy equivalent to 1000 Watts of power expended for one hour of time.

LCA – Life Cycle Assessment

LEV – Light Electric Vehicle

LFPLithium Iron Phosphate

LIB – Lithium-Ion Battery

LMO – Lithium Manganese Oxide

LV – Low Voltage is any battery operating below 60V DC.

mAh – milli Ampere-hour is one thousandth of an Ampere-hour (Ah), this is commonly used when stating the capacity of rechargeable batteries used in mobile phones. 1 mAh = 3.6 Coulombs

NiMH – Nickel Metal Hydride

Ni-Rich – lithium-ion cells that have greater than 75% Nickel in the cathode.

NMC – lithium ion cell that uses a cathode made of lithium Nickel Manganese Cobalt Oxide.

OCVOpen Circuit Voltage is the no load voltage as measured across the terminals of a cell or even across a pack.

PbAlead acid battery and commonly used as 12V starter and leisure battery.

RESS – Rechargeable Energy Storage System

RUL – Remaining Useful Life

SEI – is a passivation layer called the Solid Electrolyte Interphase and is formed on electrode surfaces from decomposition products of electrolytes. The SEI allows Li+ transport and blocks electrons in order to prevent further electrolyte decomposition and ensure continued electrochemical reactions.

SOCState of Charge is defined as the amount of charge in the cell as a percentage compared to the nominal capacity of the cell in Ah.

SOHState of Health is normally the remaining % of nominal capacity available in the cell. Technically this perhaps should be abbreviated as SOHc and SOHp is the power state of health and is the % of the original power capability of the cell.

SOP – State of Power is published by the BMS and is an estimation of the maximum power that the battery can accept or/and output at the current point in time.

SOX – abbreviation for all of the “State of …” functions that the BMS publishes to the system.

Total Energy – is the nominal cell voltage multiplied by the nominal cell capacity, both as measured at a given discharge rate.

UL – Underwriters Laboratories

Usable Energy – is the energy available within the usable SoC window of the cell or pack.

WhWatt hour is a unit of energy equivalent to one Watt of power expended for one hour of time.

XRD – X-Ray Diffraction is an analytical technique primarily used for phase identification of a crystalline material and can provide information on unit cell dimensions. This is used to understand the fundamental chemical structure in the anode and cathode materials used in a battery cell.