Abstract: A multi-way valve is provided. The multi-way valve includes a valve body and a valve core rotatably installed in the valve body. The valve body is provided with nine openings, the valve core is provided with a plurality of channels for matching with the nine openings, and the nine openings are capable of matching with the plurality of channels of the valve core to form four flow passages, the four flow passages of the multi-way valve includes at least five working modes, and the valve core is capable of rotating in the valve body to realize a switching of the multiple working modes.

Abstract: The present disclosure discloses a phase-change flame-retardant fiber material for thermal management of a lithium ion battery in a closed space and a preparation method. The phase-change flame-retardant fiber material is prepared in a coaxial electrostatic spinning manner and includes a composite phase-change fiber material PASA-TPU at a core part and a flame-retardant fiber material TB-PAN wrapping a surface of the core part. The composite phase-change fiber material is well wrapped with the flame-retardant fiber material, and the lithium ion battery wrapping the whole phase-change flame-retardant fiber material in the closed space is subjected to charge-discharge cycle; the result shows that the surface temperature of the battery can be effectively reduced by about 20° C.