An article to understand EIS lithium battery applications, with typical circuit model diagrams

An article to understand EIS lithium battery applications, with typical circuit model diagrams

1. What is electrochemical impedance spectroscopy (EIS)? 🔍

1️⃣Electrochemical impedance spectroscopy (EIS) is a non-destructive parameter determination and effective method for determining battery kinetic behavior. A small-amplitude sinusoidal voltage signal with a frequency of w1 is applied to the battery system, and the system generates a sinusoidal current response with a frequency of w2. The change in the ratio of the excitation voltage to the response current is the impedance spectrum of the electrochemical system.

A complete guide to soft pack battery assembly, a must-read for researchers

A complete guide to soft pack battery assembly, a must-read for researchers

🔋【Soft-pack battery assembly strategy: "flexible art" that researchers must see】

✨——From aluminum-plastic film to module integration, disassemble the "flexible code" of soft-pack batteries hand in hand!

A complete analysis of lithium battery internal resistance, understand the core parameters in one article!

A complete analysis of lithium battery internal resistance, understand the core parameters in one article!

[Scientific Research] A complete analysis of the internal resistance of lithium batteries: from DCR to EIS, understand the core parameters in one article!

Practical EIS data fitting, a must-have skill for battery professionals!

Practical EIS data fitting, a must-have skill for battery professionals!

1. Zview software: the golden partner of battery research

🔧 Software advantages: Accurate modeling: drag and drop equivalent circuit elements with one click, support complex models such as CPE and Warburg. Batch processing: suitable for comparing battery impedance changes under different SOC/temperatures.

Paper-level drawing: directly export fitting curves and parameter tables, eliminating Origin secondary processing.

💡 Applicable scenarios: lithium battery SEI film analysis, electrode interface dynamics research, fast charging performance evaluation

Key auxiliary materials for lithium batteries: binders

Polymer and its derivative binders

1 Cellulose binder

Sodium carboxymethyl cellulose (CMC) is a cellulose binder that has been widely studied. It is a carboxymethylated derivative of cellulose. CMC is an ionic chain polymer water-based binder that forms a transparent viscous glue after swelling with water. It has the advantages of being difficult to ferment, good stability, low price, safety and environmental protection.

Negative electrode binder performance requirements, test methods and failure mechanisms!

Binders have a low mass ratio in the electrode and do not participate in the electrochemical reaction. Their main function is to adhere the active material and the conductive agent to the current collector to keep the electrode intact . Binders affect the formation of the solid electrolyte interface (SEI) , the charge transfer inside the electrode and between the electrode - electrolyte interface , the wetting behavior of the electrode, and the cycle performance and cost of the battery .

Analysis of the influence of slurry quality on coating surface fluctuation｜‌Lithium battery production process front end (mixing/coating)

Lithium battery production process - mixing/coating

The production process of lithium batteries varies among different battery manufacturers. Generally speaking, it is divided into three stages: front, middle and back.

1. Front section: pole piece production

(Mixing, coating, tableting, baking, slitting, tableting, tab forming)

(Core link: coating)

2. Middle section: battery cell assembly

(winding or lamination, pre-packaging of cells (into shells), electrolyte injection, sealing)

(Core link: winding)

3. Post-processing (activating the battery cell)

(battery cell formation, capacity division, static placement, testing, and sorting)

(Core links: formation, volume fractionation, and testing)