Integrated heating and cooling of liquid cooling battery systems for electric tractors: A comprehensive review

This paper comprehensively reviews the research progress in battery liquid cooling thermal management systems for electric tractors (ETs) under extreme agricultural operating conditions. It systematically outlines the core distinctions between these systems and traditional electric vehicle liquid cooling approaches and highlights key design paradigms and innovative pathways tailored for this specific application. In response to challenges such as high dust concentrations, wide temperature variations, and corrosive environments inherent to agricultural settings, the review advocates for a paradigm shift from conventional hybrid cooling logic toward a fully enclosed liquid cooling architecture. This system is integrated with phase change material (PCM) and thermoelectric coolers (TECs) to enable broad-temperature-range adaptive thermal management. Furthermore, to address the continuous high-load, low-speed operational profile of ETs, which leads to a persistent mismatch between heat generation and dissipation, the review presents a critical focus on control intelligence. It elaborates on an intelligent collaborative control strategy built upon a “perception–prediction–decision–execution” closed-loop framework. Leveraging multi-source information fusion and real-time optimization, this strategy is projected to achieve precise thermal management in complex field environments. It aims to consistently maintain a maximum battery pack temperature of ≤40 °C and an inter-module temperature difference of ≤3 °C over extended operation, while simultaneously reducing system energy consumption by 15%–25%. This review provides a theoretical reference and technical framework for designing next-generation battery thermal management systems that are highly reliable and energy-efficient, specifically for harsh agricultural environments.