Creating a New Benchmark for Long-duration Lithium Battery Energy Storage

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Under the global commitment to carbon peaking and carbon neutrality, the demand for large-scale long-duration energy storage has become more prominent.

EVE Energy unveiled its CTT technology as early as October 2022 and is one of the pioneering |in the field of long-duration lithium battery energy storage.

How to make a breakthrough in long-duration lithium battery energy storage? On January 25, 2024, EVE Energy held an online release conference for its Mr. Flagship Series with the theme "Reliable Energy Storage with EVE Energy's Big Batteries", unveiling its Mr. Big battery cell and Mr. Giant system.

The Mr. Big battery cell has a high capacity of up to 628Ah, employing third-generation high-speed stacking technology, which enables an energy efficiency of 96%. The Mr. Giant system utilizes a standard 20-foot container, providing an energy capacity of 5 MWh and a high energy efficiency of 95%.

Dr. Yuan Dingding, CTO at EVE Energy's LFP battery division, explained that the newly released Mr. Flagship Series is based on electrochemical technology and theories and incorporates innovative technologies such as current collection, 3T technology, and the 14μm separator, enabling minimal heat loss between charging and discharging cycles, and the products are "more efficient, simpler, and safer", bringing in a new definition of ESS (energy storage systems) and effectively meeting the needs of large-scale long-duration energy storage development.

• The Battery Has its Vitality: Even a 1% Increase in Energy Efficiency Based on Electrochemical Principles Matters

According to calculations, a 1% increase in energy efficiency will result in an RMB 3.6 million increase in operating income for customers throughout the entire lifecycle.

To improve energy efficiency and enhance customer profitability, the EVE Energy R&D team keeps the research spirit of scientists and takes the lead in creating an innovative model of electrochemical current collection in the industry based on the principle of electrochemistry. In this process, the EVE Energy R&D team created battery tabs and poles with "golden section ratio" positions and sizes, just like opening up an "expressway" for electronics, achieved breakthrough in energy efficiency.

"The battery has its vitality, and we always make every battery with reverence." This is the corporate culture of EVE Energy.

• We guarantee long-term power supply and achieve the restoration of the Earth during each charge and discharge.

In order to solve the problem of temperature uniformity on big battery volume space, EVE Energy invented 3T technology, which is one of the core technologies in Mr flagship series.

According to Yuan Dingding, the inspiration for the revolutionary 3T technology came from the science fiction classic The Three-Body Problem. In the book, there is a weapon called the two-dimensional foil, which causes the collapse of three-dimensional space into two-dimensional space. This idea inspired the R&D team.

EVE Energy incorporated "two-dimensional foil" devices into its batteries to convert thermal diffusion in the three-dimensional space during the charge-discharge cycle of batteries into heat exchange in the two-dimensional space. It successfully solved the heat generation problem with large-capacity batteries and improved the energy efficiency of batteries and systems.

The 3T technology has reduced the temperature difference from 8°C to 1.5°C for Mr. Big batteries. It allows Mr. Giant systems to have an energy efficiency of up to 95%, with temperature differences controlled below 3°C and a 5°C decrease in the maximum temperature.

With continuous advances in lithium battery technologies, optimized energy storage solutions will unleash the full potential of PV power, ensure stable electricity supply throughout the day and night, and contribute to the restoration of the Earth.

• Build the core essence of "Reliable Energy Storage with EVE Energy's Big Batteries" to lead the world into the era of large-scale energy storage.

Based on reverence for batteries, EVE Energy consistently adheres to its original aspiration and approaches each product seriously.

Compared with the common 314Ah solution, the Mr. Big integrated system with a capacity of 628Ah has reduced the number of battery cells by 50%; in terms of pack design, the integral large pack design has been adopted for a 50% reduction in welding spots, steel strips, and end plates; at the system level, the number of information collection points and cables has been decreased by 50%.

Process innovation has always stood at the heart of EVE Energy's technological innovation. For instance, the 14μm separators selected by EVE Energy for its Mr. Flagship Series have a thickness far exceeding the industry standard and markedly enhance the safety performance of batteries.

According to Yuan Dingding, this specially coated separator technology has an excellent thermal shutdown effect. When the temperature reaches a critical value, the coating particles will melt and avoid potential hazards. Additionally, double-sided coating is conducted to ensure increased safety of separators.

As the first company to introduce and achieve swift mass production of the Mr. Flagship Series, EVE Energy has experienced a substantial leap in energy storage battery technology. This advancement will effectively propel the transformation of society towards a cleaner, more efficient, and sustainable energy storage era and further lead the world into the era of large-scale energy storage.