On November 2, 2022, AEE2022 Shanghai International New Energy Vehicle Power Battery Industry Conference was successfully concluded. The conference held extensive exchanges and discussions around CTC, CTP, CTB technology, battery pack and intelligent manufacturing technology, advanced intelligent manufacturing technology of battery tray, battery thermal management technology, and battery system management maintenance monitoring technology. As an enterprise that has been deeply engaged in the field of new energy for many years, Datang NXP was invited to attend the conference and delivered the keynote speech of BMS Management Chip with Integrated Online AC Impedance Detection Function.

At the meeting, Xiao Mengjuan, the customer manager of Datang Enzhipu, pointed out that "Datang Enzhipu integrated the EIS functions previously limited to laboratory applications into the battery management chip, which can realize online applications in the field of vehicle and energy storage, timely reflect the changes in the battery, and further improve the battery safety."

Unique EIS monitoring function improves system security in multiple dimensions

EIS (Electrochemical Impedance Spectroscopy) is the most reliable way to present the real health status of the battery. The most common EIS equipment is an electrochemical workstation worth hundreds of thousands, but it is only used in laboratories and cannot be used online in the field of vehicle/energy storage. Datang NXP DNB11xx series collects the voltage fluctuation of the corresponding frequency at both ends of the battery electrode by applying current excitation of a certain frequency to both ends of the battery electrode, and then obtains the AC impedance of the battery at this frequency through digital processing. Finally, the AC impedance at different frequencies can be plotted into an EIS diagram to obtain the online EIS monitoring function, which can realize security control from multiple dimensions.

The DNB11xx series BMS chip integrated with the online EIS impedance monitoring function can provide the battery with functions such as offline test of the battery cell, thermal runaway management of the battery cell, fault battery cell detection, online SOH detection, battery cell recycling and reuse, and wireless BMS remote diagnosis.

Among them, thermal runaway management can realize second level response, and monitor the impedance of the electric core to reflect the real-time temperature state inside the electric core; Fault cell detection can make intelligent early warning for stray cells in a module or the whole pack, and ensure safety throughout the life cycle of the new energy system. The off-line test of the battery cell can help the battery cell factory to achieve better quality control and is a protection before the battery leaves the factory. On line SOH detection can accurately evaluate the internal aging degree of the battery in a short time, at low cost and low power consumption. Wireless BMS remote diagnosis can detect the health of each battery cell and report to individual users and data centers, thus saving labor costs.

Manager Xiao said that, "We are integrating an electrochemical workstation with an average price of 300000 yuan into a chip half the size of a fingernail, so that we can monitor the health of the battery in real time throughout the life cycle of energy storage, electric vehicles and other products. Once the battery fails, the EIS will immediately display abnormalities and screen out the faulty cells from the source, so that we can no longer deal with the consequences of runaway heat passively, but actively give early warning in advance to strive for valuable maintenance and containment The time of control and escape. "

Simplify the structure and help the technical development of CTP, CTC and CTB

There are many cables and structural parts in the traditional "cell battery module battery pack" structure, which takes up space and increases the failure rate. With the rapid development of new energy vehicles, CTP, CTC and CTB technologies have been derived and are expected to become the mainstream technologies of new energy vehicles in order to continuously improve the endurance and improve the space utilization.

Datang NXP's DNB116x scheme will attach the eCCS embedded battery connection system and the sampling board directly to the battery bus bar, which can effectively save materials and space, and reduce the assembly work in the production process. Compared with the traditional battery multi string solution, the DNB1168 solution discards NTC and other peripheral circuit designs. The chip has a built-in temperature sensor, which can greatly improve the system integration while reducing the use of peripheral devices and reducing the system BOM cost. So as to fundamentally solve the space problem, better adapt the CTP, CTC and CTB technologies, and help partners to improve the utilization rate of power batteries to the extreme.

DNB116x scheme: eCCS embedded battery connection system, with the sampling board directly attached to the battery bus bar

Datang NXP is a semiconductor enterprise focusing on innovation in the field of new energy. The company has independently developed the core technologies of four leading markets, namely, impedance monitoring IP, temperature monitoring IP, voltage reference IP and HiChina Unicom IP. Through its unique technical advantages, the company's power management chip can well solve the battery safety pain points under the trend of new energy, and help partners to produce safer and more advanced battery products.