Development of a Novel Acoustic Based State-of-Charge Sensor (SOC) for Lithium-Ion Batteries

我们的建议旨在评估在锂离子电池(LIB)的结构中直接嵌入新型微型声学传感器以提供剩余能量或荷电状态(SOC)的直接测量的可行性。术语SOC定义电池中存储的能量相对于其额定容量的水平，通常以百分比(0-100%)表示。背景英国对2050年前交通运输的愿景必须在使用点实现净零。这一要求要求多个部门电气化，并使用电池技术取代传统化石燃料。一个完整的电池系统通常由数百个锂离子电池(LIB)电气组合而成。制造工艺的差异，再加上各个电池之间的互连电阻和温差的影响，使得SOC的测量成为一项极具挑战性的任务，而且目前还没有解决方案。在将电池组件扩展到完整系统时，例如电动汽车(EVS)，SoC的不确定性导致了相当大的复杂性和成本。对于未来的全电动飞机来说，这个问题更加严重。监管机构要求，由于这种不确定性，必须以额外电池容量的形式包括冗余，以确保飞机安全运行。UCL率先将超声成像用于LIBS，因为它通过一个相对低成本的平台提供非常快的(亚秒级)数据收集。在LIB中部署该技术具有挑战性，需要一种根本不同的方法。该项目将开发一种新的微型声学传感器，该传感器可以作为单个传感器或阵列嵌入LIB中，以提供一种非电化学的SOC测量手段。目的开发并验证一个概念验证演示如何将低轮廓压电换能器用作非电化学SOC传感器。将定义将传感器集成到LIB内部结构中的方法，这些方法不会对传感器和电池运行产生不利影响。应用这项研究对传感器和电池开发的重大科学贡献包括但不限于：-传感器：能够承受在锂离子电池恶劣环境中插入的低轮廓超声波传感器将突出声学换能器开发的新机遇。-电池监测：在电池的内部结构中包括声学传感器将支持新的诊断和预测方法，并将进一步支持创造电池循环经济。-电池制造：利用嵌入式仪器制造电池的能力有可能为高价值和安全关键应用创造一种新的“智能电池”分类。-电池安全：随着内部温度和气体压力的变化，测量电池微观结构和SOC的能力将突出电池设计和包括电解液、电隔离器和电极的材料选择方面的新创新。

Our proposal aims to assess the feasibility of embedding novel, miniature acoustic sensors directly within the structure of a lithium ion battery (LIB) to provide a direct measure of retained energy or state of charge (SOC). The term SOC defines the level of stored energy in the battery relative to its rated capacity and is often expressed as a percentage (0-100%). ContextThe UK's vision for transport by 2050 must be net-zero at the point of use. This requirement mandates the electrification of multiple sectors and the use of battery technology to replace traditional fossil fuels. A complete battery system will often consist of many hundreds of lithium-ion batteries (LIBs) combined electrically. Manufacturing variations, combined with the impact of interconnection resistance and temperature differences between individual batteries makes the measurement of SOC a highly challenging task and one where there is no current solution. SOC uncertainty underpins considerable complexity and cost when scaling-up battery components into complete systems, e.g., for electric vehicles (EVs). The problem is more acute for future all-electric aircraft. Regulatory bodies mandate that because of this uncertainty, redundancy must be included, in the form of additional battery capacity, to ensure safe aircraft operation. UCL has pioneered the use of ultrasound imaging to LIBs, as it provides very fast (sub-second) data collection via a relatively low-cost platform. Deploying the technique within a LIB is challenging and calls for a fundamentally different approach. This project will develop a new miniature acoustic sensor that can be embedded within the LIB as a single sensor or array to provide a non-electrochemical means of SOC measurement. ObjectiveTo develop and validate a proof-of-concept demonstration for how a low-profile piezoelectric transducer can be used as a non-electrochemical SOC sensor. Methods of integrating the sensor within the internal structure of the LIB that do not adversely affect sensor and battery operation will be defined. ApplicationsThe significant scientific contribution of this research to both sensor and battery development, includes but is not constrained too: - Sensor: Low-profile ultrasonic sensors capable of withstanding insertion within the harsh environment of a lithium-ion battery will highlight new opportunities in the development of acoustic transducers. - Battery Monitoring: The inclusion of an acoustic sensor within the internal structure of a battery will underpin new methods of diagnostics and prognostics and will further support the creation of a battery circular economy.- Battery Manufacturing: The ability to manufacture a battery with embedded instrumentation has the potential to create a new classification of 'smart battery' for high-value and safety-critical applications. - Battery Safety: The ability to measure the microstructure and SOC of the battery as internal temperature and gas pressure evolves will highlight new innovations in battery design and the selection of materials that comprise the electrolyte, electrical separator and electrodes.