Under the careful organization of Liaoning General Aviation Academy(LGAA), the thermal runawaycontainment test of the four-seater electric aircraft RX4E was successfully completed on February 17,2023. This is the first time for general aviation power lithium battery to undergo thermal runawaycontainment test in China. The success of this test not only marks thecompletion of the compliance verification of the four-seater electric aircraft RX4E power lithium battery system, but also a new breakthrough in the verification of power lithium battery in the field of general aviation. Members of the RX4Eaircraft audit team including group leader Zhang Lei, deputy group leader Xu Hai, system equipment professional group leader Wang Yanhong all witnessed the test. Zhang Qingxin, executive vice president of Liaoning General Aviation Academy, personally visited the testonsite and witnessed the test together with theaircraft audit team.

With the rapid development of China's new energy field, power lithium battery has been applied in the automobile industry on a large scale, and the energy density is getting higher and higher. As China’s first normalcategory aircraft which is designed according to the CCAR-23 standard,the four-seater electric aircraft RX4E uses lithium battery as the power source, requiring higher for the energy density of lithium battery. On the premise of the continuous improvement of the energy density, the safety of the battery has also attracted continuous attention. Thermal runawaycontainment, as the main research direction of the power battery safety, has always been the focus of safety issues.

TheFour-seaterElectricAircraft RX4E PowerLithiumBattery

Thermal runaway refers to the chain reaction phenomenon caused by various triggers, which leads to a large amount of heat and harmful gas emitted by the battery in a short period of time, and may even cause the battery fire and explosion in serious cases. There are many reasons for thermal runaway, such as overheating, overcharge, internal short circuit, collision and so on. The thermal runaway of the battery will often lead to the reaction between positive and negative electrode and electrolyte, causing large-scale internal short circuit, which will spread to other cells, and even lead to spontaneous combustion of the whole battery pack.

In order to satisfy the use needs and safety requirements of general aviation new energy aircraft, Liaoning General Aviation Academy has been committed to the safety research of general aviation electric propulsion system for many years. The design of electric aircraft power system is different from that of traditional oil-powered aircraft. As a normal aircraft,the four-seater electric aircraft RX4E exerts higher safety requirements. Under the care and guidance ofShenyang Aircraft Airworthiness Certification Center of Civil Aviation Administration of China (SYAACC), Liaoning General Aviation Academy has improved the airworthiness conformity method of electric propulsion system and power lithium battery system, and formulated the airworthiness conformity verification plan. The RX4E audit group has been focusing on the verification of the electric propulsion system and the power lithium battery system. They have discussed with the designers of our academy for many times, putting forward reasonable suggestions and opinions on the test planning, and determining the compliance verification method of the power system. To make the power lithium battery meet the airworthiness standard,the Four-seater Electric Aircraft RX4E has undertaken a lot of verification work in the airworthiness of the power lithium battery, developed the airworthiness compliance verification from various aspects such as performance and environmental adaptability, and systematically studied the thermal runaway phenomenon, temperature distribution and thermal diffusion law of the lithium battery. Through a series of tests, the first-hand information results have been obtained for the safety protection measures of general aviation power lithium battery, which has guiding significance for the key technical performance index system, detection method of power lithium battery, and the improvement of safety detection as well as evaluation system.

The Aircraft Audit Group Check the Test Parts and the Test Environment on Site

The Aircraft Audit Group Check the Test Parts and the Test Environment on Site

During the trial, the audit grouppaid close attention to the specific development of the test. The leader, deputy leader of the audit group and the leaders of our academy (LGAA) personally visited the test site. Han Chengye, who is over 70 years old, has been guiding the test on the test site, paying attention to the technical difficulties, and jointly ensuring the smooth completion of the test.

The Aircraft Audit Group Witness the Test

Thermal Runaway of Battery Packs 

Edited by Zhao Rui

Formatted by Feng Xia

First Reviewed and Proofread byGeng Hao

Further Reviewed and Proofread by Feng Xia

Finally Reviewed and Proofread by Wang Han