Noun explanation

This refers to the duration of time a battery can supply power after being fully charged, which usually depends on factors such as load power, environmental temperature, and depth of discharge.
Key influencing factors include battery capacity (Ah) and load current (A), discharge rate, temperature conditions (low temperatures can significantly shorten runtime), and aging degree (capacity attenuation).

The minimum and maximum voltage range allowed during the operation of the battery, exceeding which may lead to performance degradation or safety risks.
From a safety perspective:
Undervoltage can lead to lithium deposition on the negative electrode and SEI (Solid-Electrolyte-Interface) destruction.
Overvoltage may trigger thermal runaway, gas evolution, and electrolyte decomposition.

Refers to the application scenarios with lower power/energy demand after the battery has been retired (generally, the capacity has dropped below 80%), such as energy storage.
Extend the battery usage cycle, improve resource utilization, reduce the carbon emissions of the whole life cycle of electric vehicles, and promote the cost reduction of energy storage systems.

Self-discharge refers to the phenomenon where the charge (capacity) of a battery naturally decreases over time due to internal chemical or physical processes when no external load is connected.
Influencing Factors
Temperature: The self-discharge rate approximately doubles for every 10°C increase.
Battery Aging: The SEI (Solid Electrolyte Interface) film’s damage or thickening will exacerbate self-discharge.
State of Charge (SOC): At high voltage states, side reactions are more active, resulting in more significant self-discharge.
Material Purity: Impurities (such as Fe, Cu) can cause electrochemical corrosion, enhancing self-discharge.

A semi-empirical model refers to a mathematical model that combines physical laws with experimental data to fit the behavior of battery performance (such as capacity, internal resistance, lifespan, SOC/SOH) as it changes with usage conditions. This type of model balances the interpretability of theory with the flexibility of data-driven approaches and is widely used in fields such as battery management systems (BMS), aging prediction, and thermal management.

Sensor Off-Sets refer to the systematic error or offset between the reading values of sensors (such as voltage, current, and temperature sensors) in the battery management system (BMS) and the actual physical quantities.

Function/Role: Although it is an error, this deviation is often corrected through calibration or algorithm compensation in system design to ensure accurate SOC/SOH/temperature control judgments.

The separator is a porous film located between the positive and negative poles of the battery, allowing ions to pass through but preventing direct contact between electrons, thereby preventing short circuits.

Functions/Role:

Ensure electrical insulation within the battery
Allow lithium ions to migrate freely
Achieve ‘thermal shutdown’ function by melting closed pores at high temperatures

Severity Level indicates the severity level of battery failure in safety or performance events, commonly used in FMEA (Failure Mode and Effects Analysis) and safety assessment.

Function/Role:
Quantify the degree of failure impact to assist in decision-making.
Together with Occurrence (frequency of occurrence), Detection (detectability), they constitute RPN analysis.

Silicon is a high-capacity anode material for lithium-ion batteries, with a theoretical specific capacity of about 3579 mAh/g (compared to 372 mAh/g for graphite), which can store lithium ions by forming lithium-silicon alloys (such as Li15Si4). During the charging process, lithium ions are embedded in silicon to form an alloy; during discharge, lithium ions are extracted.

Slow Charge refers to the process of charging a battery at a lower rate (usually ≤ 0.3C), which is more gentle compared to fast charging. The slow charging process takes longer, but it can effectively reduce thermal stress and the rate of material aging.
Advantages:
The heat generation is low, and the thermal management pressure is small;
It can significantly slow down capacity degradation and extend the cycle life;
It is more conducive to maintaining electrolyte stability and preventing gas generation.

SoC (State of Charge) represents the percentage of the remaining capacity of the battery to its rated capacity, which is a core indicator for evaluating the battery’s ‘charge level’. SoC Estimation refers to the process of calculating the current remaining battery capacity through various methods and models. Since the ‘charge level’ of the battery cannot be measured directly, it needs to be indirectly estimated through external measurable parameters (such as voltage, current, temperature, etc.).

Sodium layered oxides are a type of sodium-ion battery cathode material with a layered crystal structure, usually with the general formula NaxMO₂ (M being a transition metal, such as Ni, Mn, Fe, etc.). Their structural feature is that there are sodium ion layers embedded between the transition metal oxide layers, which facilitates the insertion and extraction of sodium ions.

In the battery industry, sodium layered oxides are one of the core cathode materials for the development of sodium-ion batteries, and they have received extensive attention due to their strong sodium storage capacity, high energy density, and relatively mature preparation process. Their performance directly affects the capacity, cycle life, and cost of sodium-ion batteries, and are one of the key materials for achieving low-cost, large-scale energy storage applications.

Sodium-ion batteries are electrochemical energy storage devices that utilize the intercalation and deintercalation of sodium ions between the positive and negative electrodes to achieve charging and discharging. Similar to lithium-ion batteries, sodium resources are more abundant and the cost is lower, making them particularly suitable for low-cost, large-scale energy storage scenarios, such as peak load regulation of the power grid. They are rapidly developing in terms of performance improvement and commercialization promotion.

SOHc (State of Health – Capacity) refers to the quantitative value of the battery’s capacity health status, and the confidence interval indicates the statistical confidence range of this estimated value.
Enhancing the transparency and reliability of battery health estimation
Used in BMS systems to evaluate the uncertainty of SOH estimation algorithms
Supporting operational teams in decision-making (whether to replace, whether to continue using)

SEI is a layer of nanoscale passivation film that spontaneously forms on the negative electrode surface during the first charging process of the battery. It can prevent the electrolyte from continuing to react with the electrode, while allowing ions to penetrate, ensuring the normal operation of the battery. In lithium-ion and sodium-ion battery systems, the stability of SEI plays a crucial role in cycle life, safety, and efficiency.

Solid-state batteries use solid electrolytes to replace traditional liquid electrolytes, improving thermal stability and safety, and are expected to achieve higher energy density. They are the focus of research on the next generation of high-performance battery technology, particularly suitable for electric vehicles, high-safety energy storage, and aerospace fields.

In the battery industry, standardization refers to the establishment of unified technical specifications, testing methods, and safety requirements, in order to enhance the interoperability, safety, and market access efficiency of battery products. It is of great significance in promoting the coordinated development of the industrial chain, facilitating the implementation of technology, and promoting international trade.

State estimation algorithms are a class of mathematical tools used for real-time estimation of critical operating states of batteries (such as State of Charge SOC, State of Health SOH, etc.). Common filters include Kalman filter, Extended Kalman filter, and so on. They are the core of the battery management system (BMS) and directly affect the safety, performance management, and life prediction of the battery system.

SoC represents the percentage of the battery’s current stored energy relative to its maximum available capacity, usually expressed as 0% (fully discharged) to 100% (fully charged). SoC is a key indicator for measuring the remaining energy of the battery, similar to the fuel gauge in a car. In the battery industry, SoC is a core parameter in the Battery Management System (BMS), used for guiding energy scheduling, charge-discharge control, and system safety protection. Accurate SoC estimation is crucial for extending battery life, improving system efficiency, and ensuring operational safety, especially in applications such as electric vehicles and energy storage systems.