Innovative Non-Destructive Non-Contact Methods & Devices for Testing during Production, Optimizing Technologies, and Insuring Safety & Reliability Next Generation of Li Batteries
Authors: Shembel Elena M , Redko Vlad I , Gomez Alvarez-Arenas Tomas E , Camacho Sosa Dias Jorge , Meshri Dayal T. , Meshri Sanjay D. , Adams Robert L. , Mathur N.C. 
Published: February 2020

The safety and reliability of Li batteries are determined mainly by its basic design and chemistry. However, without adequate quality control during manufacture, defects in even the best designs can lead to inconsistent performance and early failure. Deployment of automated quality assurance technology at every stage of the manufacturing and assembly process will increase the reliability and safety of batteries while lowering overall manufacturing costs by reducing wastage and preventing defective components form being incorporated into the finished product

For the successfully coordination of stages of R&D, manufacturing and applications of the Li batteries we developed the innovative non-destructive (NDT) non-contact electromagnetic, ultrasonic, holographic interferometry, gas discharge visualization, and combined methods and equipment developed.  Developed non-destructive testing methods & devices enable to optimize the technology, and quality of initial materials, components, and cells, including in-line control during battery production. These methods allow insure the safety and reliability of the batteries and reduce the cost of production

Achievements include optimization of materials and technologies, increasing efficiency, improving reliability and safety, and reducing costs of production. These methods enable to evaluate properties and hidden defects of initial materials, including nano-structured powder of electrode materials, polymer and solid inorganic electrolytes; properties of electrodes during coating, including the interface between current collectors and electrode mass, multi-layered electrode structures, and renewable energy devices after assembly. Results allow also predict the properties of the Li batteries during applications.

Examples of applications of NDT include:

-Non-destructive non-contact testing of dry multi-layer structure.

-Non-destructive non-contact systems for determination of bulk conductivity of powdered materials.

-Electromagnetic non-destructive capacitance method for testing electromagnetic properties and chemical composition battery materials during synthesis, for example CFx

-Non-contact testing for determination of the interface resistance between current collector and active electrode mass.

-High voltage gas discharge visualization / High Voltage Electric Field Method for Quality Assurance of Hermetically Sealed Devices 

-Non-contact electromagnetic measurement of thickness and electro-physical parameters electrodes during coating.

- Non-destructive non-contact testing of the conductivity of thin film.

-Non-destructive non-contact detection of hidden faults in collector welding of batteries and ultracapacitors

-Holographic interferometry for non-destructive testing of battery components during production.

Major advantages of the non-destructive non-contact testing methods include:

-Reliability due to non-contact mode of operation.

-Efficient, fast, simple, and inexpensive to implement.

-Easy to automate. Results are obtained in real-time.

-Do not require any special protection for operators and equipment. Safe and less expensive than X-ray methods.

-Precise determination of specific parameters and defects.

-Provide 100% nondestructive control of the technological operations and the quality of the end product.

-Provide quality control of material and products for which contact methods, in principle, cannot provide reliable information due to extraneous processes at the sensor/test article interface surface.

-Provide quality control of new materials, including nanomaterials and thin-layered materials, which can be sensitive to mechanical contact

Developed NDT methods and equipment are based on the interaction of different vector, and scalar fields with the test article:

- Wave acoustic fields of different polarization.

- Potential electrical and magnetic fields.

- Vector eddy magnetic fields.

- Gradient heat fields (infra-red spectrum).

- Electron emission fields.

- Glow fields of high voltage pulse discharges

During presentation will be presented examples of using the innovative non-destructive testing methods during Li batteries development and production, description of the NDT methods and equipment. Some examples of the NDT equipment are presented on the photos.

Figure 1