电池成组液流热控及其整车热力集成协同增效机理研究

As an important guarantee of electric vehicles (EV) for high performance, service life and reliability, the battery thermal management (BTM) in different extreme climates become a necessary technology. For this reason, a fundamental research theme of the enhancement of packing battery thermal management by hydronic circulation and the synergy of vehicle thermal integration is proposed. Through the liquid flow the thermal integration in whole EV links battery heating and cooling with cabin heating, ventilating and air conditioning (HVAC). Researching work focus on designing and developing a new hydronic heat exchange structure for battery temperature regulation and their multiple packing, a creative phase change material (PCM) thermal cascade storage structure by mixing more melting points and stacking encapsulated ball/beam/plate, in which the heat transfer enhancement mechanism will be investigated in different size, structure，scale and condition. Based on the above design, a complex integrated system will be builted for hybrid heating and cooling batteries and cabin HVAC, which involves complicated integration, incentive thermal promotion and process control from multiple thermal systems by means of liquid circulation. So the collaborative optimization is necessary to save energy, to guarantee battery suitable temperature and ensure human comfort. The thermal interaction effect of many thermal units, conjugation synergy, thermal behaviors and rule, control strategy and so on will be explored in the different condition, such as vehicle running, electric power, thermal load and HVAC, etc. Especially, the thermal interaction in cold start, high load, transient load and other dynamic conditions will be found. Thus, the goal of this proposal is to systematically study and to present an analytical method and solution to understand coordinated vehicle thermal management containing BTM and HVAC, to establish the effect relation of much more factors and to scheme control strategy. This work will promote the progress of EV and guide a effective way in much more weathers (especially extreme cold) and break through the the limitation of traditional air cooling of BTM and realize the hydronic refined control for low energy consumption by using more thermal sources and recycling wasted heat in EVs.

电池热管理是电动汽车效能、寿命和可靠性的重要保证，解决不同气候下电动汽车冷暖热力支撑已成重要环节和关键。为此，提出动力电池液流热控强化传热及其整车热力集成协同增效主题，液流循环热力集成协同再利用，实现电池装备和暖通空调冷暖双控。探索设计新型液体循环电池换热结构和成组层叠高效传热，以及PCM梯级蓄热结构和多熔点搭构传热强化，研究各构件多尺度、多形态、多工况的强化传热作用机理。在组成构件强化传热基础上，探索多热力系统耦合、热力强化和流程控制等问题，界定车辆行驶过程、电力与热力过程、车辆空调过程关联关系，以及多热力系统和过程集成的协同控制机制，建立控制因素的相互作用关系，确立优化可控性。通过耦合协同研究，揭示车辆工况下液流循环热力集成体系中节能增效过程关联的本质特征、控制策略和方法，拓展电动系统热控能力，突破传统空气冷却局限性，为实现多种气候环境下电动汽车热力支撑及其技术进步奠定理论基础。

针对电动汽车电池组热管理和整车集成热管理，开展新型电池成组液流热控及其整车热力集成协同增效机制与机理的研究，特别是其中的新型电池组态与液流传热构件设计、热管理体系构形设计及其传热强化，以及热管理过程高效热传输和组态电池热控性与温控性增效。通过液流循环热力集成，实现整车多系统协同和冷暖过程的低能耗，突破以往热管理局限性，应对复杂环境条件电动汽车热控支撑与热安全。首先，设计新型电池组液流换热结构，如多形态微小槽道、导热片围绕、成组层叠、组合传热等，认识电池组态传热强化机理，提出减小组内液流体积的轻量化、温均化等强化传热等创新实现。再者，深入研究基于车载的蓄热结构，创新设计离散结构的球形和超薄扁管等PCM封装构形堆积、管束组合蓄能构造，提出多熔点搭构（混/序堆，管束列构）、液流温向、温度梯级和组合分布等增效蓄能传热控制策略机制，研究各构件多尺度、多形态、多工况的强化传热作用机理。其次，在完成基本构件和组元强化传热基础上，建立典型车载多热力系统集成热管理集成体系，探索多热力系统耦合、热力强化和流程控制，研究关联关系、作用机理、控变协同、低能耗机制、控制策略和前馈/反馈管控性等，提出包括热泵辅助、散热热流变、多温位热源迁移等电池冷暖温变性和组态温均性协同控制保证，以及热传输高效和低能耗集成优控机制。最后，结合整车行驶工况，构建整车电动力-热动力集成热管理系统，综合研究协同节能增效机理与控制机制，界定车辆行驶、电/热动力、冷暖热泵等关联性，以及多热力系统集成机制及可控因素相互作用规律，揭示液流循环热力集成体系优控的节能增效本质特征，提出温位、流变、多元/流程组配及其热传输时变性等多场耦合重整热流变的主控要素协同，构建集成热管理优控模式及其综合设计分析平台方法。由此，进一步拓展电动系统热控能力，突破传统热管理局限性，为实现电动汽车及其动力电池热管理科技进步奠定基础。