How to Charge Li-Ion with a Parasitic Load

Contributed commentary by Isidor Buchmann, CEO & Founder, Cadex Electronics Inc.

Charging a battery is simple but the complexity rises when a parasitic load is present during charge. Depending on battery chemistry, the charge process goes through several stages, and with lithium-ion Stage 1 consists of a constant current (CC) charge that brings the battery to roughly 70 percent state-of-charge (SoC). The cell reaches 4.20V/cell, a common voltage limit for Li-ion, after which Stage 2 continues by applying a constant voltage (CV) charge. The current begins to drop as the battery saturates. Full-charge is reached when the current decreases to typically 0.05C, which is one-twentieth of the rated ampere-hour. Li-ion cannot absorb overcharge and no charge is applied in Stage 3. Figure 1 illustrates typical voltage, current and capacity signatures of the CCCV charge. Read more about How to Charge Li-Ion with a Parasitic Load

Transparent Processes from the Powder to the Cell

Contributed Commentary by Maximilian Sackerer, Senior Business Consultant for Battery and Fuel Cell Manufacturing, Siemens AG

Powerful lithium-ion batteries are a key component both in electric vehicles and for the decentralized storage of electricity from renewable energy sources. Acceptance by car drivers depends on the capacity, safety, durability, and costs of the batteries and this, in turn, will determine the future of electric mobility. All these properties have to be brought up to a worldwide competitive level in the mass production of lithium-ion cells, and continuously improved. Read more about Transparent Processes from the Powder to the Cell

Printed and Bio-Sourced Lithium Ion Batteries for Wearable Technologies

Commentary Contributed by O. El Baradai, J. Schleuniger*, S. Fricke, C. Bosshard, CSEM SA, Switzerland

 

Continuous progress in electronic devices, in particular portable electronic gadgets, is creating new opportunities and products to revolutionize our daily life. However, these ubiquitous portable devices with different functions require highly efficient power sources to sustain their use. Batteries are essential for powering such portable electronic devices. A battery is a closed system in which energy is stored in chemical form, and it is converted to electrical energy by connecting the battery to an external load to complete the circuit, causing electric current to flow between the anode and cathode. Electronics have traditionally been designed around commercial batteries:prismatic, cylindrical, and coin cells, which are bulky, rigid, and non-flexible, making them unsuitable for powering flexible electronics. Read more about Printed and Bio-Sourced Lithium Ion Batteries for Wearable Technologies

Optimal Rheology, Better Electrodes: Understanding the Links Between Battery Slurry Properties and Electrode Performance

Commentary Contributed by Dr. John Duffy, Product Marketing Manager, Malvern Panalytical

The multistep process used to manufacture battery electrodes must be closely controlled to produce components that deliver desirable electrochemical performance. In order to achieve this, the rheological properties of the slurries used during processing must be optimized, since these properties affect important characteristics such as slurry stability, ease of mixing, and coating performance, which impact on the properties of the finished electrode. Electrode slurries typically include electrochemically active materials, conductive additives, and binders, in addition to solvent, and both composition and the properties of each component can have an impact on the rheology of the resulting suspension. However, so too can the processing conditions applied. Each process step subjects a slurry to different stresses and each optimally calls for different rheological characteristics. Read more about Optimal Rheology, Better Electrodes: Understanding the Links Between Battery Slurry Properties and Electrode Performance

Battery Rapid-Test Methods

Contributed Commentary by Isidor Buchmann, CEO & Founder, Cadex Electronics, Inc.

A battery resembles a living organism that cannot be measured; only estimated by diagnostics similar to a doctor examining a patient. The accuracy of rapid-testing varies according to symptoms that change with state-of-charge (SoC), agitation after charge and discharge, temperature and storage. A rapid-test must distinguish between a good battery that is partially charged and a weak pack that is fully charged. Both will deliver similar runtimes in the hands of the user but have different performance levels. Read more about Battery Rapid-Test Methods

The Role of Power Electronics and Energy Harvesting in the Future of Batteries

Contributed Commentary by Brian Zahnstecher, Sr. Member of the IEEE, and the Principal of PowerRox

In just about any application in the world of electronics, energy storage plays an important factor.  Whether it be a battery that limits charge time or life of portable electronics, a Telecom’s capacity to sustain hold-up in a catastrophic situation, a data center’s ability to reduce the power bill, or a sensor’s ability to capture, analyze and transmit key telemetry data from a very harsh, potentially inaccessible environment.  In just about any market or vertical we have encountered at PowerRox or in previous, professional lives, there is a maniacal focus on increasing the density of energy storage solutions (as well as power electronics density) in electronic gizmos.  Thanks to some very high-profile incidents with lithium-ion batteries, safety is a receiving an ever more scrutinizing eye, but this can still come somewhat at odds with the desire to push energy densities. Read more about The Role of Power Electronics and Energy Harvesting in the Future of Batteries

Batteries by Design: Unique Perspectives Through Multi-Scale Imaging

Commentary contributed by Jeff Gelb, Carl Zeiss Microscopy

Batteries are complex systems. From the protective mechanisms in the packaging to the finest details of the active materials, a wide range of structures must work together in order for a battery to function properly. As consumers and government agencies alike demand higher energy densities at lower costs per kwh, optimizing these complex systems is of critical importance to furthering battery technologies. In parallel with optimizing the functionality of the cells, it is equally important to ensure the safe and reliable operation of the battery product, during normal use, storage, or extreme conditions. Addressing these issues requires a full understanding of a battery’s life cycle, from formation through performance, so that root-causes can be identified and modifications to structure and/or chemistry may be made. Read more about Batteries by Design: Unique Perspectives Through Multi-Scale Imaging