二十年高能密度电活性聚合物及复合薄膜储能换能产品的研发促成我们模块化大容量锂塑电池与模块化高灵敏度压塑电芯走向商业化 (The Business of Innovations of Modular Large-Capacity Li-Polymer Cell and Modular High-Sensitivity Piezo-Polymer Cell via 20-Year R&D of High Energy Density Electroactive Polymers and TFC Membrane Energy Storage and Conversion)

关键词: 储能 (Energy Storage); 电池 (Battery); 电容 (Capacitor); 电活性材料 (Electroactive Material); 薄膜 (Thin Film); 纳米复合材料(NanoComposite); 逾渗 (Percolation)

我们对电活性聚合物及复合薄膜材料储能换能产品的研发开始于上世纪九十年代。二十年来, 全球电活性储能换能产品的研究与商业化取得了长足的进展。我们在不断的尝试与探索中不断改进, 不断创新, 寻找产品工业化成功的希望, 同时也积累了很多产品研发与市场需求的宝贵经验, 为电活性聚合物及复合薄膜材料储能换能的商业成功打下了坚实的基础。二十年来, 我们提出了很多尝试性的设想并努力去实现, 不断接受前人的经验与教训, 寻找合适的合作伙伴, 面向市场与客户, 走进消费者, 坚持从“技术研发主导”到“产品设计主导”的创新思想, 坚持 “以人为本” 的产品设计理念, 促成我们具有核心技术自主知识产权及核心产品模块化大容量锂塑电池 (Modular Large-Capacity Li-Polymer Cell)与模块化高灵敏度压塑电芯 (Modular High-Sensitivity Pizeo-Polymer Cell) 走向商业化, 并提供客户储能与换能解决方案及优质服务。当回首, 经验与教训同在, 工程科学研究与产品研发更需要市场与时间来作检验。

Power vs. Energy Delivery Profile Technologies Ragone Chart
(Alternative and Multiscale Power and Energy Storage Technologies, Systems and Markets)

Evolution of Capacitor Technology Having a Close Relationship with Materials and Packaging Development

Polymer Based Nanodielectric Composites, in Advances in Ceramics – Electric and Magnetic Ceramics, Bio ceramics, Ceramics and Environment, Ch. 7, 15-132 (General Electric).

Toward High Energy Density Capacity with Graceful Failure: Great deal of knowledge has been acquired about nanodielectrics; however, there is still no breakthrough in increasing dielectric strength and permittivity simultaneously, not to mention keeping low cost and product consistence from bench, pilot to full scale manufacturing of nanomaterials, approaching the business success. There remain a lot of challenges and opportunities for scientists and engineers to solve the practical problems, not to mention only using nanotechnology for commercialization.

  ·有耗電容器 (Lossy Capacitor) 与集成储能电力电子热管理系统 (Integral Energy Storage Power Electronics Heat Transfer and System Thermal Management): The non-ideal capacitor called a lossy capacitor due to the energy lost as heat due to the resistance or others, distinguished from the hysteresis energy loss, effectively includes both capacitors and resistors. A lossy capacitor can be represented as a series or parallel or combination of capacitance C and resistance R including the loss.

Capacitors generate heat via dielectric losses and connection losses between the dielectric and the terminals. These losses can be modeled as a series combination of the capacitor and ESR. Thermal changes can be calculated simply heat generated minus the heat dissipated. The heat rise during operation can then be expressed as a thermal resistance with units of 0C/watt.

DC Link and AC filter capacitors with very high current requirements are common in power inverters and power supplies. Capacitor packaging plays a major consideration in system design; some people use a single large unit, while others prefer bundling smaller capacitors into banks. The packaging decision also affects the appropriate cooling method. For applications such as medium voltage motor drives and wind or solar power systems, designers have a choice between film and electrolytic capacitors. Cost, volumetric efficiency, and maintainability are the major factors in this decision. As metallized film capacitor manufacturing techniques and materials continue to improve, their volumetric efficiency and cost have become increasingly attractive. As many power systems are installed in applications that make servicing difficult, it is important to select the right capacitor(s) and to ensure they meet the appropriate cooling guidelines.

An increasing number of power electronic systems require film with foil and metallized film capacitors to handle high currents. These systems generally rely on water cooled chill plates for thermal management of their components (IGBTs and capacitors). However, integrating water cooling to film capacitors is a technique that until recently was reserved for the Induction Heating market. Water cooled capacitors have a forty year history of reliability in these industries. Effective heat transfer using various types of integral water cooling methods for film capacitors significantly influences capacitor performance. Direct water cooled capacitors occupy much less volume than their air cooled counterparts. The application of liquid cooling for polymer film dielectric capacitors for AC and for DC applications indicates that liquid cooled capacitors will become more common as power electronics’ energy densities increase.

1. M. Zahn, Charge injection and transport in a lossy capacitor stressed by a Marx generator, 1st International Conference on Conduction and Breakdown in Solid Dielectrics, July 4-8, 1983, Toulouse, France; IEEE Transactions on Electrical Insulation, Vol. EI-19, No. 3, June, 1984.
2. M. Zahn, Electromagnetic Field Theory: A problem Solving Approach, Wiley 2nd Ed., 2003.
3. http://ocw.mit.edu/resources/res-6-002-electromagnetic-field-theory-a-problem-solving-approach-spring-2008/index.htm
4. D.D.L. Chung, Functional Materials: Electrical, Dielectric, Electromagnetic, Optical and Magnetic Applications, (With Companion Solution Manual), World Scientific Publishing Company, 2010.
5. Hari Singh Nalwa, Handbook of Low and High Dielectric Constant Materials and Their Applications: Materials and Processing, Phenomena, Properties and Applications, Academic Press, 1st Ed., 1999.
6. http://www.sciencemag.org/content/313/5785/334.full
7. http://www.sciencemag.org/content/321/5890/821.short
8. http://onlinelibrary.wiley.com/doi/10.1002/adma.200802902/abstract
9. R. Kerrigan, Film capacitors with integral water cooling provide efficient heat transfer and system thermal management, www.nwl.com/files/file/Capacitors/NWLPCIM2010DOC(1).pdf

储能晶界层电容 (GBLC) 与 逾渗电容 (PC) VS. 商业成功的多层薄膜电容 (MLCC and TFC)储能:

Comparison of a) diagram of a multilayer capacitor (MLC or MLCC): gray and white regions represent metallic and dielectric layers, respectively, b) diagram of a boundary layer capacitor (BLC or GBLC): white areas represent reduced (semiconductor) ferroelectric grains while gray lines correspond to oxidized (insulator) grain boundaries, and c) diagram of a percolative capacitor (PC): gray and white regions represent metallic or conductive / semiconducting and dielectric insulating material, respectively [42], Ph.D. Thesis.

? Electroactive Doped Ceramics: From EEStor’s Nano-BT Capacitor (ZENN Motor) to A123 Systems’ Nano-LFP Battery (MIT Spin-off, Fisker Automotive) :

储能电容器的创新以美国 EEstor 公司计划研制生产的 Electrical Energy Storage Units (EESU)最具代表性。EESU 可以认为属于晶界层电容 (Grain Boundary Layer Capacitor, GBLC) 体系, 利用组份改性的钛酸钡 BaTiO3 (Composition Modified Barium Titanate, CMBT), 复合高介电常数聚合物 (High k Polymer) , 做成Nano-CMBT/polymer 样品。根据最新技术专家的现场报告(ZENN Motor Company Releases Consultant’s Report) 及多年的技术经验, 也可以认为属于逾渗电容 (Percolative Capacitor, PC)体系。和锂离子电池正极材料磷酸亚铁锂A123 Systems’ Nano-LFP类似的材料制备工艺, 进行导电内搀杂(Intrinsically Doped) 或导电外包覆(Extrinsically Coated) 并做成纳米颗粒, EEstor 公司采用湿化学工艺, 搀杂改性的高介电常数 BaTiO3 纳米颗粒材料, 包覆厚度为10nm 的氧化铝与钙镁硅酸盐物质形成芯-壳结构, 最后制备成超高压超薄平板电容器组件。不考虑无机陶瓷与有机聚合物实际的电场强度, 据相关专利称, EESU在承受500MV/m (V/mm) 电场强度的同时介电常数er 达到19,818, 从而达到非常高的储能密度 (402 Wh/kg), 目前市场上铅酸电池的储能密度一般只能达到20Wh/kg, 而先进的锂离子电池的储能密度一般为100-265Wh/kg, 153kg的电容器可供10kW功率的电动汽车, 以96km/h速度使用5h, 行驶480km 。ZENN Motor 公司投资并将拥有EEStor 储能电容及EESU技术在电动车 (NEV) 的使用权。

无论是哪种晶界层材料或逾渗材料, 若要用于下一代储能动力电容介质, 都需要具有高介电常数和高击穿电压。如果能够通过对晶界的改性和包覆使其介质强度大大提高, 将很可能成为动力电容材料的重要组成部分。但受到晶界层材料内搀杂与外包覆等工艺技术的限制, 譬如容易出现内搀杂难以控制和成分不均或外包裹过厚和包裹不均等现象, 同时要达到纳米级颗粒及微米级成膜厚度也面临挑战, 更不要说保持大批量产品质量的一致性。回顾从二战后发现第一个铁电陶瓷氧化物BaTiO3后对晶界层材料的不断努力, 七十年来的历史经验与教训很容易明白从实验室的DEMO 到工业化大规模生产还有太长太长的路要走。

ZENN Motor Company Releases Consultant’s Report






TRS Technologies, Inc.


? Electroactive Solid Solution Ceramics: From TRS or Recapping’s Nano-PZT Capacitor to 3M’s NCM or Envia Systems’ Nano-HCMR Battery (ANL Spin-off):

从二战后发现第一个铁电陶瓷氧化物BaTiO3后对铁电陶瓷及其固溶体的不断改进工作, 七十年来的历史经验与教训很容易明白从实验室的DEMO 到工业化大规模生产同样还有很长的路要走。

逾渗 应用? 电活性材料 ? 电活性复合材料 ? 电池储能 ? 科学 or 商业

Percolation Applications ? Electroactive Materials ? Electroactive Composites ? Battery Energy Storage ? Science or Business

逾渗电活性复合材料储能电池 (Enhanced electrical electronic or ionic percolation of electroactive materials and composites and energy storage in battery )

电子或离子电导率, Electrical (electronic or ionic) conductivity :

介电常数或电容率诱电率, Dielectric constant (permittivity) :




Intrinsically Doping or Extrinsically Coating: Grain Boundary Layer or Percolation

Bound charges in polycrystalline or nanocrystalline semiconducting or organic semiconductor materials can be thought of in different ways. Real materials are usually highly disordered. An exciton within a diffusion length of a percolation path can contribute to photocurrent in blends.

? Li-ion Battery Percolation and Construction of Structural Battery Energy Storage:

Even in more complicated situations than the one shown, the decisive steps in Li-batteries are ion transport through the electrolyte, phase transfer to the electrode and chemical diffusion in there. The equations refer to small signal behavior. Size reduction acts on the transport coefficients as well as on the proportionality factors containing distances directly.

Enhanced Electrode Electronic Percolation in Lithium-ion Battery

Enhanced Electrolyte Ionic Percolation in Plastic Lithium-ion Battery: Transformation of a soft matter solid electrolyte such as polymer electrolyte with a non-percolative arrangement of highly disordered (higher ion mobility) regions to a percolative arrangement of disordered regions as in gel electrolytes. Percolative network of disordered regions provide fast ion transport pathways for the mobile ion.





? 模块化大容量锂塑电芯 (Modular Large-Capacity Li-Polymer Cell) 与集成储能电池热管理系统(Integral Energy Storage Battery Heat Transfer and System Thermal Management):

Without adequate battery thermal management, calls for a ten-year life span for some high energy density Li-ion battery in various thermal environments are unrealistic. For example, lithium-ion battery capacity decreases with temperature, and battery degrades faster at higher temperatures. And over time, useful energy from the battery decreases with exposure to elevated temperatures, which impacts on driving range and performance of vehicle. The environments also significantly influence the lifetime of stationary batteries. Battery temperature is important, and temperature affects battery:

1. Operation of the electrochemical system;
2. Round trip efficiency;
3. Charge acceptance;
4. Power and energy availability;
5. Safety and reliability;
6. Calendar life and life cycle cost.

The battery temperature affects system performance, reliability, safety, and life cycle (thus cost). To meet the customer requirements, the cells must be kept in a thermally noncritical state in all operating conditions. Therefore, efficient battery pack thermal management is needed, i.e.,

1. Regulate pack to operate in the desired temperature range, i.e., 20-35 0C for optimum performance / life;
2. Reduce uneven temperature distribution, i.e., less than 3-4 0C in a pack to avoid unbalanced electrical modules / pack and thus avoid reduced performance;
3. Eliminate potential hazards related to uncontrolled temperatures – thermal runaway.

The requirements placed on the thermal management of Li-ion batteries are clearly beyond the capabilities of conventional engine cooling. There are three different approaches to cooling a Li-ion battery, considering on cell structures, cell types and potential cooling paths, i.e., integration of battery cooling into vehicle cooling system.

1. Using cooled air;
2. Using a supplementary evaporator in the form of a cooling plate installed within the battery;
3. A heat exchanger (or “chiller”) transfers the low temperature produced by the evaporated refrigerant to a second circuit (secondary circuit) that, in turn, cools the cells in the battery. This too necessitates the installation of a cooling plate within the battery.

Life trade off analysis of life expectation in various thermal environments indicates that the liquid-cooled battery can use 12% fewer cells and still achieve a 10-year life, compared with no cooling or thermal management. Air cooling using low-resistance cells also seems appealing from a thermal / life perspective; however, this battery has the highest cell costs of the four options shown due to the cost of its high excess power. Liquid cooling with chilled fluid has a longer battery life.





Li-ion battery cooling: more than just cooling.


20-Year R&D History:

 ·1993, Ionomer-coated and dispersed inorganic nanoparticles formulation and coating;
 ·1994, Enhanced thermoplastic single-ion conductor and solid-state Li-ion polymer battery (PLIB);
 ·1995, Modified aramid fiber fabric separator for nickel-hydrogen battery;
 ·1996, Insulating polymer coatings for high-temperature self-solderable enameled round winding wires (QA/UEW, class 180);
 ·1997, Tri-layer all-plastic Li-ion battery (PLIB);
 ·1998, Polymer-metal electrode interface engineering;
 ·1999, Enhanced plastic adhesion and laminate packaging;
 ·1999, Electronic-ionic hybrid conductor;
 ·2000, Fast-response solid-state Li-ion electrochemical cell;
 ·2001, Thin-film cell assembly, filling and sealing;
 ·2001, In-situ polymerization technology of gel polymer;
 ·2002, High energy density plastic thin-film capacitor with graceful failure;
 ·2001, 2D huge p-conjugated delocalized charge macromolecules (superelectronic polarized polymer and graphene) as high density charge and energy storage materials;
 ·2002, High-k polymer nanocomposite dielectric capacitor energy storage;
 ·2003, High energy density plastic transducer with graceful failure;
 ·2004, Low-voltage driven polymer nanocomposite membrane transducer;
 ·2005, Pre-charging method and pre-charged thin-film built-in bias integration;
 ·2006, Pre-charged transistor circuitry and integrated analog front end (iAFE);
 ·2007, Electret and piezo-polymer thin films and piezo-cables;
 ·2007, Piezo-polymer film cellular foam transducer;
 ·2008, Electro-spinning nanofiber nonwoven fabrics;
 ·2008, Hybrid nanofiber microporous membrane;
 ·2007, Engineering solutions for scalable battery energy storage;
 ·2007, Fiber surface modification and coating and fiber prepregs for pre-impregnated, fiber-reinforced laminate composites;
 ·2008, Robustly nano-tailored structure for high-throughput high-temperature piezoelectric films;
 ·2009, Piezo-polymer cell;
 ·2008, TFC membrane electrode and current collector prepregs;
 ·2008, TFC membrane electrolyte and separator;
 ·2009, Gelled electrolyte enhancement;
 ·2009, TFC membrane coating, laminate packaging and cell stacking;
 ·2008, Pre-charged electrode;
 ·2010, High-capacity cathode;
 ·2010, High-temperature (1800C) TFC plastic electrolyte high-power-density cell packaging;
 ·2008, Thin-layered bi-cell configuration;
 ·2010, Current collector pre-treatment and electrode slurry formulation and mixing;
 ·2008, TFC electrode membrane and slitting;
 ·2009, Bi-cell packaging and stacking;
 ·2011, Battery cell formation, degassing, aging, capacity grading and sorting;
 ·2010, Li-polymer cell design and packaging;
 ·2012, PLIB pouch cell production assembly line;