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

我们的提案旨在评估将新型微型声学传感器直接嵌入锂离子电池（LIB）结构中的可行性，以提供保留能量或荷电状态（SOC）的直接测量。术语SOC定义了电池中存储的能量相对于其额定容量的水平，并且通常表示为百分比（0-100%）。英国到2050年的交通愿景必须在使用点实现净零。这一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）组成。制造差异，加上互连电阻和单个电池之间的温度差异的影响，使得SOC的测量成为一项极具挑战性的任务，并且目前没有解决方案。当将电池组件按比例放大为完整的系统时，SOC的不确定性支撑了相当大的复杂性和成本，例如，电动汽车（EV）。对于未来的全电动飞机来说，这个问题更加严重。由于这种不确定性，监管机构要求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LIB，因为它通过相对低成本的平台提供非常快速（亚秒级）的数据收集。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，可作为单个传感器或阵列嵌入LIB中，以提供SOC测量的非电化学方法。目的开发并验证一种低轮廓压电换能器如何用作非电化学SOC传感器的概念验证演示。将定义在LIB的内部结构内集成传感器的方法，这些方法不会对传感器和电池操作产生不利影响。该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：能够承受锂离子电池恶劣环境中插入的低剖面超声波传感器将突出声学换能器开发的新机会。- 电池监测：在电池内部结构中包含声学传感器将支持新的诊断和诊断方法，并将进一步支持电池循环经济的创建。电池制造：制造具有嵌入式仪器的电池的能力有可能为高价值和安全关键型应用创造一种新的“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质，电隔膜和电极的材料选择的新创新。

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.