CATL Freevoy battery optimized for EREV and PHEV vehicles

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The hottest vehicles in the Chinese new car market are EREVs (extended range electric vehicles) and PHEVs (plug-in hybrids). The difference between them can be filled in with technical jargon, but in general, an EREV has a battery large enough to handle most daily driving needs without any external assistance but also has an internal combustion range extender engine to recharge the battery while driving when necessary. . BYD has models for sale in China that claim a total range of 2,100 kilometers (1,305 miles). Not only do they have large battery packs to make this possible, the gasoline engines that complement the batteries are some of the most efficient ever built, outperforming even the vaunted Toyota Prius in this regard.

CATL, the world’s largest lithium-ion battery manufacturer, noticed this trend toward extended-range electric vehicles and decided it wanted to join the party (BYD makes its own batteries, for the most part). On 24 October 2024, it launched the Freevoy Super Hybrid Battery, the world’s first hybrid vehicle battery to achieve a pure electric range of over 400 km and 4C ultra-fast charging, which it says will herald a new era of high capacity EREV and PHEV batteries and transform this sector of the new vehicle market. .

CATL Freevoy addresses range concerns

CATL noted that these vehicles are gaining prominence in the new energy vehicle market because consumers have consistently expressed frustration with battery-powered electric vehicles that suffer from short range, slow charging, and decreased cold-weather performance. These factors have emerged as critical challenges that require immediate solutions. Designed specifically for EREV and PHEV vehicles, CATL’s Freevoy battery frees drivers from the constant need to charge, a common shortcoming of today’s hybrid vehicles. The new battery allows many drivers to commute for a week before recharging if necessary. Additionally, it offers amazing charging speeds that can provide an additional 280 kilometers of range in just 10 minutes using a Level 3 charger. This virtually eliminates range anxiety for owners of these cars.

Behind the impressive range and ultra-fast charging are a number of technological breakthroughs, according to Gao Huan, chief technology officer at China electric vehicle company CATL. In his presentation during the launch of the Freevoy battery, Zhao said that the Freevoy battery includes cathode material surface modification technology, combined with an innovative high-voltage electrolyte formulation, to create a nanoscale protective layer. This effectively reduces side reactions within the active layer.

Incorporating highly active excited state molecules into the cathode material greatly enhances the transfer efficiency of lithium ions within the material. Thanks to the upgraded control algorithm and hardware of the battery management system, the control accuracy of the charge state of the Freevoy battery has been increased by 40 percent and the overall electric utilization rate has increased by more than 10 percent. Combined, these improvements bring a range on battery power alone to over 400 kilometres.

This means about 250 miles. Even using the more stringent EPA standard rather than the optimistic WLTP standard that is the standard in China, this still indicates that a vehicle equipped with a Freevoy battery would likely be rated between 180 and 200 miles by the EPA ). PHEV models available today in the U.S. have a range of only about 30 to 50 miles, according to the EPA. Do you think buyers would be more interested in these cars if they could travel 4-6 times farther?

Better building management system

CATL performed a model data analysis on the charge/discharge polarization characteristics of the Freevoy battery to accurately predict the future discharge capacity of the battery and created a multi-level energy prediction and control strategy that improved the energy performance of hybrid vehicles by 20%. In addition, CATL has successfully applied 4C ultra-fast charging technology to the Freevoy battery, adding a range of over 280 kilometers in 10 minutes of fast charging. Lithium ions are easily transported through the application of fast cathode ion conductive coating technology, second-generation graphite for fast charging, new anode nano-coating technologies, multi-layer electrode design, and a new superconducting electrolyte formulation, allowing hybrid vehicles to deliver the ultimate charging experience, over On par with pure electric cars.

Until now, one of the downsides to PHEVs was that they were very slow to charge, which limited the amount of time they could run on battery power alone on long trips. Now EREV and PHEV drivers can charge at roughly the same time that drivers of conventional vehicles need to refuel. Let’s face it – most of us take about the same amount of time to use the bathroom and grab a snack at rest stops. Now drivers using the CATL Freevoy battery can stop, recharge and get back on the road without having to watch their gasoline-powered friends disappear over the horizon while they wait for the charge to finish. (Note: CATL did not mention the power level of the chargers it used to analyze Freevoy battery performance.)

Utilizing sodium ion technology

Sodium-ion batteries are less affected by cold temperatures. To take advantage of this feature, CATL added some sodium-ion battery cells to the Freevoy’s battery to break the low-temperature limitations of conventional new energy vehicles. It achieves discharging capacity in extremely cold environments up to -40°C, reduces charging capacity to -30°C, and maintains a smooth driving experience up to -20°C compared to normal temperatures.

To further improve Freevoy’s low-temperature performance, CATL has implemented three key technological innovations centered around sodium-ion battery technology. First, using CATL’s leading AB battery system integration technology, Freevoy combines sodium-ion and lithium-ion batteries in a specific ratio and arrangement, with mixed, series and parallel connections to enhance the low-temperature range by 5%. Secondly, CATL takes the sodium ion battery as a state of charge meter to monitor the AB battery system to help calibrate the charge level of the lithium ion battery. This raises the system’s control accuracy by 30%, adding more than 10 kilometers to the pure electric range.

To address the inherent disparities in performance between lithium-ion and sodium-ion batteries at low temperatures, CATL has developed BMS technology that is accurate across a wide temperature range. This technology implements targeted zone management of distinct chemical systems around the clock, effectively alleviating problems such as inaccurate charge prediction or decreased power performance in harsh high- and low-temperature environments.

CATL Freevoy is already in production

CATL has established a comprehensive reliability management and evaluation system, starting from material selection and molecular design, including multi-level protection structures, extreme manufacturing processes, comprehensive testing and validation, and big data-based early warning mechanisms. Freevoy has already been used in many different models manufactured by different brands, including Li Auto, AVATR, and others. By 2025, 30 hybrid vehicle models from brands including Geely, Chery, GAC and Voyah are scheduled to be built using the CATL Freevoy battery. With this new battery technology, CATL continues to push the boundaries of technological innovation and accelerate the transition to universal electrification.

At CleanTechnica, we continue to insist that the batteries that will power our electric cars in 2030 have not yet been invented. CATL shows that significant progress toward those future batteries is possible and that there is more to come. The electric vehicle revolution has only just begun, at least in many countries outside North America or Europe.