马广青 熊飞 朱林培

摘 要：为保证纯电动汽车低温性能，低温下需对动力电池制定有效的加热措施。文章基于Amesim，建立了某款动力电池系统冷却液加热模型。对比分析了低温下定目标水温与变目标水温对动力电池系统快充时间、温差、能耗影响，快充SOC5%-95%定目标水温快充时间比变目标水温快约21min，电池包最大温差增加3℃，能耗增加0.42kWh。在次基础上分析了不同定目标水温对动力电池性能影响，定目标水温每增加10℃，快充时间减少2-3min，电池包最大温差增加约1℃。最后对比了降档策策略对快充时间影响，直接降档与关闭加热器降档快充时间、电池包最大温差基本相同，能耗减小5.6%，档位波动次数减小37%。

关键词：动力电池;低温加热;快充时间;仿真分析

Abstract： In order to ensure the low temperature performance of electric vehicles， effective heating measures should be made for the power battery at low temperature. Based on Amesim， the coolant heating model of a power battery system was established. The effects of fixedcoolant target temperature and variable coolanttarget temperature on DC charging time， temperature difference and energy consumption of power battery system are analyzedat low temperature， the DC charging time of fixed coolant target temperature is about 21min faster than that of variable coolant target temperature， the maximum temperature difference of the battery pack increases by 3℃， and the energy consumption increases by0. 42kWh. Then， the influence of different target coolant temperature on the performance of power battery is analyzed， for every 10℃ increase of target coolant temperature， the DC charging time decreases by 2-3min， and the maximum temperature difference of battery pack increases by about 1℃. Finally， the paper compares the effect of downshift strategy of the heater on DC charging time， the direct downshift compared with off heater downshiftthe DC charging time and the maximum temperature difference of the battery pack are same， the energy consumption is reduced by 5.6% and the number of gear fluctuations is reduced by 37%.

Keywords： Power battery; Low temperature heating; DC charging time; Simulation analysis

前言

近年来随着化石能源的日益消耗，人们环保意思的提高，相对传统汽车产生CO、HC及NOX、微粒、臭气等排气污染，纯电动汽车作为一种无污染、低噪声、能源效率高的新型交通工具，越来越受到人们的关注及应用。动力电池作为纯电动汽车的关键部件之一，其性能表现直接影响纯电动汽车的整车性能。温度对动力电池尤其三元锂离子动力电池工作特性产生影响，高温下动力电池循环寿命减低、充放电功率受限、充电时间延长;低温下动力电池内部活性物质显著下降，电池内阻增加、充放电功率及容量明显降低，极端情况下，可导致动力电池无法充放电等情况，温度对动力电池的影响，造成整车寿命下降、充电时间延长、续驶里程下降，尤其低温下影响显著[电动汽车动力电池热性能仿真研究]。……