Many electric vehicles are powered by lithium batterie that rely on cobalt—a scarce, expensive metal with high environmental and social costs. A team of researchers from Japanese and French universities has now developed a practical nickel-based electrode material that opens new avenues to cobalt-free batteries for electric vehicles.

The researchers detailed their findings in a study published in the journal Energy Storage Materials.

“There is an undeniable need for cobalt-free, high-energy electrode materials for lithium batterie,” said Naoaki Yabuuchi from Yokohama National University.

Lithium batterie can be recharged when lithium ions flow from a positively charged electrode to a negatively charged electrode. In most lithium batterie for portable electronics, the positive electrode contains lithium cobalt oxide (LiCoO2), a chemical compound that offers high stability and energy density.

However, the limited, fraught supply chain of cobalt creates a bottleneck for large-scale batteries, including the ones used in electric vehicles. In addition, cobalt extraction generates toxic waste that contaminates land, air, and water.

To address these issues, lithium nickel oxide (LiNiO2)—which is similar in structure to LiCoO2—often serves as a cobalt-free alternative for electrode material. However, key instability issues plague the compound, specifically a gradual loss of capacity at the high-voltage region, which is associated with nickel-ion migration.

To improve electrode reversibility, nickel ions have been partially substituted by other metal ions, including reintroduced cobalt ions as well as manganese, aluminum and magnesium, to create “nickel-enriched layered materials” to serve as positive electrode materials.

“So far, 10–20 percent cobalt ions were necessary for nickel-based electrode materials,” Yabuuchi said. This, according to Yabuuchi, is still too much, and a unified understanding of how metal substitution can improve the process has not yet been established.

To address this knowledge gap, Yabuuchi and collaborators dug deeper into the problematic phase transition. When lithium ions leave the cathode under the influence of an external field, nickel ions migrate to specific sites within the lithium layers. Although this process is reversible, the reversibility gradually degrades through continuous cycles until the capacity is completely lost—a phenomenon not seen in cobalt-ion migration.

Previous studies reported that tungsten doping in LiNiO2 is an efficient approach to suppressing the detrimental phase transitions at high-voltage regions. Yabuuchi and collaborators tested the hypothesis that heavy, expensive tungsten ions could be substituted with other elements, specifically phosphorous—a lighter, more abundant element.

After detailed analysis on LiNiO2 integrated with nanosized lithium phosphate (Li3PO4), the researchers observed that, under certain conditions, problematic nickel-ion migration was effectively suppressed due to repulsive electrostatic interaction from the extra nickel ions within the Li layers.

Moreover, from these findings, Li-deficient LiNiO2, Li0.975Ni1.025O2, with the extra nickel ions in Li layers, is also synthesized using a simple methodology without phosphorus integration. Results also showed how Li0.975Ni1.025O2 can effectively mitigate unfavorable nickel-ion migration, and deliver consistent reversibility without cobalt ions.

“These findings open a new direction to develop high performance and practical cobalt-free nickel-based electrode materials with an extremely simple and cost-effective methodology,” Yabuuchi said. “This material achieved the ultimate goal for high-performance nickel-based electrode materials.”

In future endeavors, the researchers plan to investigate the feasibility of a nickel-free material to support lithium-ion batteries.

More information: Itsuki Konuma et al, Unified understanding and mitigation of detrimental phase transition in cobalt-free LiNiO2, Energy Storage Materials (2024). DOI: 10.1016/j.ensm.2024.103200

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In the realm of powering electronic devices, voltage regulation stands as a crucial aspect, especially when it comes to the ubiquitous 5V batteries. From portable gadgets to intricate systems, the ability to maintain a stable voltage is paramount.

What is Voltage Regulation?

Voltage regulation is the process of maintaining a stable output voltage regardless of fluctuations in input voltage or changes in load conditions.

Significance of Voltage Regulation in 5V Battery

In the context of 5V batteries, voltage regulation ensures that the output voltage remains close to 5 volts, crucial for the smooth operation of electronic devices. Stable power output is essential for ensuring device performance and functionality. Voltage regulation also protects devices from voltage fluctuations, prolongs battery life, and enhances energy efficiency. By using voltage regulators, battery voltage can be converted to a stable voltage required by the device, safeguarding it from high or low voltage impacts. This regulation also aids in improving overall energy utilization, adapting to different load demands, and ensuring devices operate at a stable voltage under varying working conditions.

Common Voltage Regulation Techniques

Linear Regulator: Linear regulators stabilize output voltage by consuming excess voltage. They are simple, cost-effective, and stable but less efficient, especially when input voltage exceeds output voltage. Efficiency typically ranges between 60% to 80%.

What Is a Linear Voltage Regulator?

Switching Regulator: Switching regulators adjust input voltage to obtain a stable output voltage using switch principles. They offer higher efficiency by minimizing energy loss but are complex and expensive.

What is a Switching Regulator?

Boost/Buck Converter: Boost converters increase input voltage to the desired output voltage, while buck converters decrease it. They offer stable output under different conditions and efficiency depends on load, input, and output voltage conditions.

For voltage regulation in 5V batteries, a common method is using a buck converter to lower higher battery voltage to 5V. Buck converters adjust input voltage by controlling switch conduction time, ensuring stable output voltage regardless of battery voltage changes.

Switched-mode Power Supply: Switched-mode power supplies adjust output voltage by controlling switch conduction time. They are efficient and flexible, widely used in various applications.

In summary, choosing a voltage regulation technique depends on specific application requirements and budget considerations. Higher efficiency techniques generally offer better performance and energy utilization but may entail higher costs and design complexities. As technology evolves and industries embrace new paradigms, the role of voltage regulation in 5V batteries will continue to evolve.

For more insights into cutting-edge batterysolutions, visit Himax.

With the continuous advancement of science and technology, the development of medical equipment increasingly relies on advanced electronic technology. Because of their low voltage, light weight and portability, 5V batteries have become an ideal power source choice in the medical field, especially for driving small electronic components and portable medical equipment. They can provide reliable power to equipment and enhance patient care and medical equipment. of portability. Here are some examples of medical devices using 5V batteries:

Portable Monitors

Devices that measure and display vital signs such as blood pressure, heart rate, and oxygen saturation may use 5V batteries for their portability and efficient power consumption.

Blood Glucose Meters

Many glucose meters, used by individuals with diabetes to monitor their blood sugar levels, are designed to be compact and portable. Some of these devices utilize 5V batteries.

Thermometers

Electronic thermometers, especially those designed for home use, may incorporate 5V batteries to power the temperature sensing and display components.

Infusion Pumps

Some types of infusion pumps, which deliver fluids, including medications or nutrients, to a patient’s body, may use 5V batteries for their control systems.

Handheld Diagnostic Devices

Certain handheld diagnostic devices, like point-of-care testing equipment, may rely on 5V batteries to power their electronic components.

It’s important to note that the specific voltage requirements can vary between different devices. If you would like to inquire about battery solutions for medical portable devices, please feel free to contact us.

Overcharging refers to the process of continuing to apply current to a battery after it has reached its charging capacity limit, causing the battery to continue accepting a charge.

In general, 5V lithium-ion batteries are relatively safe under normal charging conditions because modern electronic devices are typically equipped with charging management circuits that can monitor and control the battery’s charging status to prevent overcharging. However, occasional instances of overcharging may occur.

What are the possible phenomena when a 5V lithium-ion battery is overcharged?

Overheating

Overcharging can lead to the battery overheating, accelerating internal chemical reactions, aging the battery, and compromising its performance. Additionally, overheating may result in safety issues, such as the expansion or even rupture of the battery casing.

Gas Generation

In extreme cases, overcharging may cause the generation of gas inside the battery, leading to the expansion or rupture of the battery casing. Gas generation may also react with components in the electrolyte, further damaging the battery.

Loss of Electrolyte

Electrolyte is essential for the normal operation of the battery, and its loss can result in decreased battery performance, reduced capacity, and even battery failure.

Reduced Battery Lifespan

Overcharging accelerates the aging process of the battery, leading to a shortened lifespan. The cycle life of the battery (the number of charge-discharge cycles) may also significantly decrease.

To avoid overcharging a 5V battery, consider the following practices:

Use Original or Compliant Chargers: Use chargers provided by the original manufacturer or those that comply with relevant standards. This ensures that the charger is designed to meet the battery specifications and incorporates appropriate charging management systems.

Use Appropriate Power Adapters: Ensure that the selected power adapter’s output voltage and current match the battery specifications. Avoid using chargers from unknown sources or those that are not compliant.

Avoid Using Damaged Charging Devices: Refrain from using damaged or broken charging devices, as this may cause unstable current and voltage, increasing the risk of overcharging.

Follow User Instructions: Read and follow the user instructions for both the device and the battery, understanding the maximum allowable charging voltage and current. Ensure compliance with the instructions during use.

Avoid Prolonged Charging: When the battery is fully charged, try to avoid leaving the device plugged in for an extended period. Although modern devices often have charging management systems, it’s still advisable to prevent prolonged charging.

Regularly Check Device and Battery Status: Periodically check the status of the device and the battery to ensure there are no obvious signs of damage or abnormalities. If issues are detected, promptly replace or repair the device.

Use Batteries with Charging Protection: Some batteries come with built-in protection circuits to prevent overcharging. When purchasing batteries, consider selecting models equipped with charging protection features.

Overall, effective battery management is crucial to ensure the safe operation of your 5v batteries and devices, if you are looking for high quality, reliable 5v battery management solutions, please feel free to contact us.