探索电动汽车大容量锂离子电池BMS系统详解与入门

需积分: 50 96 浏览量更新于2024-07-19 3 收藏 3.53MB PDF 举报

电动汽车的动力电池管理系统（Battery Management System, BMS）是电动汽车核心技术的重要组成部分，它负责监控、管理和保护车载锂离子电池组的性能与安全。在大型锂离子电池包的应用中，BMS的设计与实现显得尤为关键。《大型锂离子电池包的电池管理系统》一书由Davide Andrea编著，收录于Artechouse出版社，具有Library of Congress和British Library的目录记录，版权信息保障了知识的独占性和完整性。 BMS的主要功能包括以下几个方面： 1. **电池状态监控**：BMS能够实时监测电池单体的电压、电流、温度、荷电状态（State of Charge, SOC）和健康状态（State of Health, SOH），确保电池在工作范围内运行，避免过充、过放或过热等问题。 2. **均衡管理**：通过精确控制电池单元间的充电电流，保持电池组整体性能一致，延长电池寿命。电池容量不一致时，BMS能进行自动或手动均衡操作。 3. **故障检测与诊断**：当检测到电池异常时，BMS会识别并记录故障类型，提供报警和保护，如短路、过压、欠压等，保证行车安全。 4. **充放电控制**：根据车辆需求和电池状态，BMS会智能调整充放电策略，确保高效且安全的能源转换。 5. **能量管理**：通过优化电池的充放电策略，BMS帮助电动汽车实现最佳的能量利用率，并在必要时限制功率输出以适应各种驾驶条件。 6. **热管理**：考虑到电池的热效应，BMS还负责控制散热，防止电池温度过高或过低，从而保护电池性能和寿命。 7. **安全防护**：在极端情况下，如碰撞或火灾风险，BMS会触发保护措施，如切断电池电源，防止进一步损害。设计一款大型锂离子电池包的BMS需要对电池技术有深入理解，包括电池物理、化学特性的认识，以及电力电子、控制算法等多领域的知识。此外，随着技术的发展，BMS还需要集成高级功能，如无线通信能力，以便与车辆其他系统（如动力总成、充电设施）协同工作，提高电动汽车的整体性能和用户体验。《大型锂离子电池包的电池管理系统》是一本详尽介绍了电池管理系统的理论与实践的实用指南，适合电池工程师、电动汽车制造商、科研人员和学生参考，是电动汽车行业发展不可或缺的技术参考资料。

packs (especially LiFePO

and lithium-titanate) compared to standard (LiCoO

)

Li-Ion cells.

1.2.3 Safety

Li-Ion cells perform magnificently, but are rather unforgiving if operated outside a

rather tight safe operating area (SOA), with consequences ranging from the annoy

ing to the dangerous.

In most cases the only effect is simply that the life of the cell is reduced, or that

the cells are damaged, with no safety issues. However, abusing a Li-Ion cell in partic

ular ways can be extremely dangerous and can result in physical damage (piercing,

crushing) and/or overheating (from over-voltage, over-current, or external heat).

I have witnessed in horror the result of making a short circuit across a “safe”

LiFePO

battery: the cells expelled their contents very violently, in succession, like

firecrackers (Figures 1.3 and 1.4). Thanks to safety procedures in place at the time,

the battery was on a cart and next to an exit, which allowed the technicians to

quickly wheel it outside.

I also have performed a forensic analysis on a Prius converted to PHEV

(Figure 1.5), which caught on fire due to arcing inside it Li-Ion traction pack (see

Section 6.1.1.5).

No one got hurt in either event. In both cases, human error was at fault: poor

mechanical design and bad manufacturing processes (no quality control and distrac-

tions present in the manufacturing area). In neither case was a BMS to blame.

Those are extreme examples. However unlikely such events may be, let them

serve as a warning of how dangerous large Li-Ion batteries can be. Be safe when

working on such a battery.

4 Introduction

Figure 1.3 Putting out a Li-Ion battery on fire after a direct short circuit across it.

tery, know that procedure by heart, and be prepared to complete it within 10

seconds of the starting event.

1.2.4 Safe Operating Area

The SOA of Li-Ion cells is bound by current, temperature, and voltage.

•

Li-Ion cells will be quickly damaged and may burst into flames if overcharged

above a certain voltage.

•

Most Li-Ion cells will be damaged if allowed to be discharged below a certain

voltage.

•

The lifetime of Li-Ion cells will be drastically reduced if discharged outside a

certain temperature range, or charged outside an even tighter temperature

range.

•

Li-Ion cells can experience a thermal runaway and ignite if allowed to exceed a

safe temperature; even cells that are not prone to thermal runaway may con

tain an organic electrolyte, which will fuel flames.

•

Li-Ion cells’ lifetime will be reduced if discharged at too high a current, or

charged too fast.

•

Li-Ion cells may be damaged if operated at high pulse currents for more than a

few seconds.

These limits vary considerably with the chemistry of the cell. For example, stan-

dard Li-Ion cells (LiC

) without any additional protection mechanisms will go into

thermal runaway at a relatively low temperature, while LiFePO

cells are intrinsi-

cally immune to thermal runaway. These limits vary to a certain extend with the

manufacturer. For example, A123 and K2 manufacture very similar small cylindri-

cal cells, yet the A123 cells can be discharged down to 0V with no ill effects, while

the K2 cells may not be discharged below 1.8V (Figure 1.6).

1.2.5 Efficiency

A significant advantage of Li-Ion cells compared to other chemistries is that they are

particularly efficient in energy and charge.

1.2.5.1 Energy

The resistance of a Li-Ion cells is quite low (especially in a so-called power cell),

which means that little I

R power is wasted in heat inside of them. For example, the

M1 26,650 cells from A123 (used in power tools and PHEV conversion), have a typ

ical resistance of 10 mΩ; when loaded at 1C (2.3A), they waste P = 2.3

*10mΩ =

53 mW, while delivering P = 2.3A * 3.2V = 7.6W, which is an efficiency of 99.3%

(98.6% round trip when considering both charging and discharging).

At higher currents the energy efficiency of a cell goes down. More energy is

wasted in heat inside the cell (across its resistance) leaving less energy available to do

work outside the cell.

6 Introduction

剩余301页未读，继续阅读

lindian033

粉丝: 2
资源: 7

探索电动汽车大容量锂离子电池BMS系统详解与入门

电动汽车BMS核心技术解析：超越软硬件的电池管理

电动汽车动力电池管理：BMS系统自检与关键指标分析

电动汽车锂电池BMS技术趋势：解决安全与一致性挑战

解析电动汽车动力电池BMS的技术

电动汽车动力锂电池BMS管理系统综述.pdf

电动汽车动力电池的理论内涵及实践应用——评《电动汽车动力电池应用技术》.pdf

电动汽车动力电池管理系统

动力电池BMS10串设计指南

锂电池基础知识生产流程及BMS系统电动汽车用动力电池动力电池行业研究报告（12个）.zip

汽车电子中的基于ISO26262的动力电池BMS解决方案

最新资源