Abstract: With the rapid development of artificial intelligence and Internet of Things technology, smart wearable technology has gradually matured and been widely used, and the demand for the sustainability and independence of smart wearable device energy supply in various industries is getting higher and higher. The limited design space of wearable devices is not conducive to the expansion of energy storage devices, and redundant power supplies will inevitably bring electronic waste and environmental damage. Therefore, the need to develop technologies that directly obtain energy from human physiology and the external environment so as to strengthen the independence of energy supply is becoming increasingly urgent.
Currently, energy such as solar energy, ambient thermal energy, electromagnetic energy, and mechanical energy is harvested by micro-energy harvesting technology from the surrounding environment. Co-generator technology supplies energy to wearable electronic devices, and provides energy to energy supply equipment by converting micro energy in the external environment into electrical energy, such as friction generators, thermoelectric generators, mechanical and piezoelectric generators and solar cells. At the same time, the development of wearable technology is inseparable from the synergy with energy storage technology. Second, since micro-energy harvesting and energy storage require corresponding control and regulation circuits, it is necessary to develop system-level energy management strategies to improve their efficiency, reliability and practicality in wearable systems.
With the development of energy supply technology, self-powered sensors can provide power to sensing devices. To enable implantable and sustainable wearable electronics, self-powered sensor technology integrates self-powering and sensing, solving the drawback that most current sensors cannot work independently and must rely on an external power supply. Using new micro-energy harvesting or energy storage or both, sensing devices can continuously collect more operational data in harsh environments and build powerful data analysis libraries.
Technical research based on micro-energy harvesting and energy storage technology is an important foundation for the energy supply of wearable devices. In the future, researchers can collect more other clean energy and store it. While the diversity of energy supply technologies is expanded, the energy utilization efficiency is greatly increased. This offers great potential for energy supply for wearable devices.
Flexible and small-scale energy-integrated devices have greatly promoted the innovative research of energy supply technology in wearable devices. So far, miniaturized devices, high-power efficient conversion, energy storage enhancement and other technologies have greatly promoted the application of wearable devices in industries such as inspection. In the future, a large number of wearable device energy supply operation data can be obtained, the operation law of the equipment can be more deeply grasped, and combined with intelligent algorithm analysis, a more intelligent, reliable, convenient and energy-saving wearable continuous energy supply device can be designed.

Key words: wearable devices, energy harvesting and energy storage, self-powered sensor, integration technology [1] 张铁龙.新能源风力发电技术研究[J].技术与市场 ,2020,27(11):116,118.
ZHANG Tielong. Research on new energy wind power generation technology[J]. Technology and Market, 2020, 27(11): 116, 118.
[2] 周迎春,胡志军,肖慧慧.太阳能发电并网系统关键技术[J].电子世界,2017(9):150.
ZHOU Yingchun, HU Zhijun, XIAO Huihui. Key techno-logies of solar power grid connection system[J]. Electronics World, 2017 (9): 150.
[3] 吕艳芳,李佳冀,潘思言,等.涡激振动发电装置及其关键技术[J].装备制造技术,2020(1):161-165.
Lü Yanfang, LI Jiaji, PAN Siyan, et al. Vortex induced vibration generator and its key technology[J]. Equipment Manufacturing Technology, 2020 (1): 161-165.
[4] 屈高阳.地热能发电技术在地区供暖中的应用[J].宁波职业技术学院学报,2019,23(1):105-108.
QU Gaoyang. Application of geothermal power generation technology in regional heating[J]. Journal of Ningbo Poly-technic, 2019, 23(1): 105-108.
[5] WANG C Y, XIA K L, WANG H M, et al. Advanced carbon for flexible and wearable electronics[J]. Advanced Materials, 2019, 31(9): 1801072.
[6] DONG K, WU Z Y, DENG J A, et al. A stretchable yarn embedded triboelectric nanogenerator as electronic skin for biomechanical energy harvesting and multifunctional pressure sensing[J]. Advanced Materials, 2018, 30(43): 1804944.
[7] SERAG E, EL-MAGHRABY A, EL NEMR A. Recent developments in the application of carbon-based nanoma-terials in implantable and wearable enzyme-biofuel cells[J]. Carbon Letters, 2022, 32(2): 395-412.
[8] LÜ J, YIN L, CHEN X H, et al. Wearable biosuper-capacitor: Harvesting and storing energy from sweat[J]. Advanced Functional Materials, 2021, 31(38): 2102915.
[9] LU X, QU H, SKOROBOGATIY M. Piezoelectric micros-tructured fibers via drawing of multimaterial preforms[J]. Scientific Reports, 2017, 7: 2907.
[10] PARRILLA M, DE WAEL K. Wearable self-powered electrochemical devices for continuous health management[J]. Advanced Functional Materials, 2021, 31(50): 2107042.
[11] JIA Y H, JIANG Q L, SUN H D, et al. Wearable thermoelectric materials and devices for self-powered electronic systems[J]. Advanced Materials, 2021, 33(42): 2102990.
[12] ROUDNESHIN M, SAYRAFIAN K, AGHDAM A G. A machine learning approach to the estimation of near-optimal electrostatic force in micro energy-harvesters[C]// Proceedings of the 7th IEEE Interna-tional Conference on Wireless for Space and Extreme Environments, Ottawa: Electr Network, 2019: 71-75.
[13] FAN F R, TIAN Z Q, WANG Z L. Flexible triboelectric generator[J]. Nano Energy, 2012, 1(2): 328-334.
[14] WANG Y, SHI Y, MEI D, et al. Wearable thermoe-lectric generator to harvest body heat for powering a miniaturized accelerometer[J]. Applied Energy, 2018, 215: 690-698.
[15] ZHANG X S, BRUGGER J R, KIM B. A silk-fibroin-based transparent triboelectric generator suitable for autonomous sensor network[J]. Nano Energy, 2016, 20: 37-47.
[16] JUNG W S, LEE M J, KANG M G, et al. Powerful curved piezoelectric generator for wearable applications[J]. Nano Energy, 2015, 13: 174-181.
[17] PU X, SONG W, LIU M, et al. Wearable power-textiles by integrating fabric triboelectric nanogenerators and fiber-shaped dye-sensitized solar cells[J]. Advanced Energy Materials, 2016, 6(20): 1601048.
[18] GHOMIAN T, MEHRAEEN S. Survey of energy scaven-ging for wearable and implantable devices[J]. Energy, 2019, 178: 33-49.
[19] JUNG S, LEE J, HYEON T, et al. Fabric-based integrated energy devices for wearable activity monitors[J]. Advanced Materials, 2014, 26(36): 6329-6334.
[20] ZHAO L M, LI H, MENG J P, et al. The recent advances in self-powered medical information sensors[J]. InfoMat, 2020, 2(1): 212-234.
[21] 刘津池,于淼,王侠.摩擦纳米发电机在织物基智能可穿戴中的应用[J].现代纺织技术,2020,28(4):53-63.
LIU Jinchi, YU Miao, WANG Xia. Application of tribo-lectric nanogeneratorsin fabric-based intelligent wearable device[J]. Advanced Textile Technology, 2020, 28(4): 53-63.
[22] WANG Z F, RUAN Z H, NG W S, et al. Integrating a triboelectric nanogenerator and a zinc-ion battery on a designed flexible 3D spacer fabric[J]. Small Methods, 2018, 2(10): 1800150.
[23] QIU Q, ZHU M M, LI Z L, et al. Highly flexible, breathable, tailorable and washable power generation fabrics for wearable electronics[J]. Nano Energy, 2019, 58: 750-758.
[24] SHAIKH F K, ZEADALLY S. Energy harvesting in wireless sensor networks: A comprehensive review[J]. Renewable and Sustainable Energy Reviews, 2016, 55: 1041-1054.
[25] ROUDNESHIN M, SAYRAFIAN K, AGHDAM A G. Adaptive estimation of near-optimal electrostatic force in micro energy-harvesters[C]// Proceedings of the 4th IEEE Conference on Control Technology and Applications,Montreal: Electr Network, 2020: 782-786.
[26] IRANMANESH E, LI W W, ZHOU H, et al. A system-level approach towards a hybrid energy harvesting glove[J]. Sensors, 2021, 21(16): 5349.
[27] DUAN X F, REN J C, ZHANG X W, et al. Room-temperature thermoelectric conversion by dipole-enhanced rashba spin-orbit coupling[J]. Cell Reports Physical Science, 2021, 2(1): 100284.
[28] TOMONO T. A new approach for body heat energy harvesting[J]. International Journal of Energy Research, 2019, 43(9): 4967-4975.
[29] LIU Y J, YIN L, ZHANG W W, et al. A wearable real-time power supply with a Mg ₃ Bi ₂ -based thermoelectric module[J]. Cell Reports Physical Science, 2021, 2(5): 100412.
[30] CHONG Y W, ISMAIL W, KO K, et al. Energy harves-ting for wearable devices: A review[J]. IEEE Sensors Journal, 2019, 19(20): 9047-9062.
[31] NOGHABAEI S M, RADIN R L, SAVARIA Y, et al. A high-sensitivity wide input-power-range ultra-low-power RF energy harvester for IOT applications[J]. IEEE Transactions on Circuits and Systems I, 2022, 69(1): 440-451.
[32] MA J G. Harvesting ambient RF energies for powering wearable devices[J]. IEEE Transactions on Microwave Theory and Techniques, 2020, 68(9): 3605.
[33] 刘霞.全柔性整流器可将无线信号转为电能未来有望为可穿戴设备供电[N].科技日报,2019-02-01(2).
LIU Xia. Fully flexible rectifier converts wireless signals into electricity, promising future for powering wearable devices[N]. Science and Technology Daily, 2019-02-01(2)
[34] 王文琦,费廷伟,王学勇,等.智能穿戴设备及其能量收集技术简述[J].军民两用技术与产品,2019(4):59-62.
WANG Wenqi, FEI Tingwei, WANG Xueyong, et al. A brief description of smart wearable devices and their energy harvesting technology[J]. Dual Use Technologies & Products, 2019 (4): 59-62.
[35] 刘竞雅.智能穿戴设备的能源解决方案[J].电源技术,2017,41(5):834-836.
LIU Jingya. Energy solutions for smart wearable electronics[J]. Chinese Journal of Power Sources, 2017, 41(5): 834-836.
[36] LANDERER D, BAHRO D, ROHM H, et al. Solar glasses: A case study on semitransparent organic solar cells for self-powered, smart, wearable devices[J]. Energy Technology, 2017, 5(11): 1936-1945.
[37] 王远飞.可穿戴设备的太阳能微能量采集与管理研究[D].成都:电子科技大学,2020.
WANG Yuanfei. Research on Solar Micro-Energy Harvesting and Management of Wearable Devices[D].Chengdu: University of Electronic Science and Technology of China, 2020.
[38] KOMAZAKI Y, KANAZAWA K, NOBESHIMA T, et al. Energy harvesting by ambient humidity variation with continuous milliampere current output and energy storage[J]. Sustainable Energy & Fuels, 2021, 5(14): 3570-3577.
[39] YANG C, HUANG Y X, CHENG H H, et al. Hygroelectric generators: Rollable, stretchable, and reconfigurable graphene hygroelectric generators[J]. Advanced Materials, 2019, 31(2): 1970013.
[40] SHAO C X, GAO J, XU T, et al. Wearable fiber form hygroelectric generator[J]. Nano Energy, 2018, 53: 698-705.
[41] REN G P, WANG Z, ZHANG B T, et al. A facile and sustainable hygroelectric generator using whole-cell Geobacter sulfurreducens[J]. Nano Energy, 2021, 89: 106361.
[42] ZHANG X Z, CHEN X, QU Y L, et al. Fabricating high performance multi-functional hygroelectric generator through a biomimic approach[J]. Nano Energy, 2022, 98: 107241.
[43] FENG J Y, XIAO M, HUI Z, et al. High-performance magnesium-carbon nanofiber hygroelectric generator based on interface-mediation-enhanced capacitive discharging effect[J]. Acs Applied Materials & Interfaces, 2020, 12(21): 24289-24297.
[44] LEE T, KIM I, KIM D. Flexible hybrid nanogenerator for self-powered weather and healthcare monitoring sensor[J]. Advanced Electronic Materials, 2021, 7(12): 2100785.
[45] YU B Y, WANG Z H, JU L, et al. Flexible and wearable hybrid RF and solar energy harvesting system[J]. IEEE Transactions on Antennas and Propagation, 2022, 70(3): 2223-2233.
[46] LI Z J, LUO J, XIE S R, et al. Instantaneous peak 2.1 W-level hybrid energy harvesting from human motions for self-charging battery-powered electronics[J]. Nano Energy, 2021, 81: 105629.
[47] ZHANG S, XIA Q C, MA S Y, et al. Current advances and challenges in nanosheet-based wearable power supply devices[J]. iScience, 2021, 24(12): 103477.
[48] RAJENDRAN V, MOHAN A M V, JAYARAMAN M, et al. All-printed, interdigitated, freestanding serpentine interconnects based flexible solid state supercapacitor for self powered wearable electronics[J]. Nano Energy, 2019, 65: 104055.
[49] VAGHASIYA J V C, MAYORGA-MARTINEZ C, VYSKOCIL J, et al. Flexible wearable MXene Ti ₃ C ₂ -based power patch running on sweat[J]. Biosensors and Bioelectronics, 2022, 205: 114092.
[50] JIANG Z Y, ZHAO Y Y, HUANG W B, et al. Hierarchically nanobranch structured freestanding metallic mesh electrode for high-performance transparent flexible supercapacitor[J]. Journal of Alloys and Compounds, 2021, 861: 158593.
[51] YAN K, LI J A, PAN L J, et al. Inkjet printing for flexible and wearable electronics[J]. APL Materials, 2020, 8(12): 120705.
[52] ZENG X L, PENG R H, FAN Z Y, et al. Self-powered and wearable biosensors for healthcare[J]. Materials Today Energy, 2022, 23: 100900.
[53] YIN L, KIM K N, TRIFONOV A, et al. Designing wearable microgrids: Towards autonomous sustainable on-body energy management[J]. Energy & Environmental Science, 2022, 15(1): 82-101.
[54] BENHAMMANE M, NOTTON G, PICHENOT G, et al. Overview of electrical power models for concentrated photovoltaic systems and development of a new operational model with easily accessible inputs[J]. Renewable and Sustainable Energy Reviews, 2021, 135: 110221.
[55] MILLAH I S, SUBROTO R K, CHANG Y W, et al. Investigation of maximum power point tracking of different kinds of solar panels under partial shading conditions[J]. IEEE Transactions on Industry Applications, 2021, 57(1): 17-25.
[56] YAO Z L, LIU T. Boost and full-bridge integrated converter for wide input-voltage range application[J]. International Transactions on Electrical Energy Systems, 2021, 31(7): e12916.
[57] KAWAGUCHI A, UCHIYAMA H, MATSUNAGA M, et al. Simple and highly efficient intermittent operation circuit for triboelectric nanogenerator toward wearable electronic applications[J]. Applied Physics Express, 2021, 14(5): 057001.
[58] MAYER P, MAGNO M, BENINI L, et al. A low power and smart power unit for kinetic self-sustainable wearable devices[C]// Proceedings of the 27th IEEE International Conference on Electronics, Circuits and Systems, Glasgow: Electr Network, 2020: 1-4.
[59] MALAKOOTI M H, ZADAN M, KAZEM N, et al. Liquid metal composites for flexible thermoelectric energy harvesting[C]// Proceedings of the Conference on Behavior and Mechanics of Multifunctional Materials XV,Istanbul: Electr Network, 2021: 11589.
[60] XIAO L, MENG Y, TIAN X B, et al. Energy allocation for activity recognition in wearable devices with kinetic energy harvesting[J]. Software: Practice and Experience, 2021, 51(11): 2185-2202.
[61] LATTANZI E, DONATI M, FRESCHI V. Exploring artificial neural networks efficiency in tiny wearable devices for human activity recognition[J]. Sensors, 2022, 22(7): 2637.
[62] WANG H, FENG Y Y, GAO J, et al. Metallic-ion controlled dynamic bonds to co-harvest isomerization energy and bond enthalpy for high-energy output of flexible self-heated textile[J]. Advanced Science, 9(20): 2201657.
[63] WANG J, ZHANG H L, XIE Y H, et al. Smart network node based on hybrid nanogenerator for self-powered multifunctional sensing[J]. Nano Energy, 2017, 33: 418-426.
[64] BEYAZ M I, AHMED N. A belt-integrated piezoelectric energy harvester for wearable electronic devices[J]. Ferroelectrics, 2021, 585(1): 187-197.
[65] KRISHNAMOORTHY K, PAZHAMALAI P, MANOHA-RAN S, et al. Recent trends, challenges, and perspectives in piezoelectric-driven self-chargeable electrochemical super-capacitors[J]. Carbon Energy, 2022, 4(5): 833-855.
[66] GILSHTEYN E P, AMANBAEV D, SILIBIN M V, et al. Flexible self-powered piezo-supercapacitor system for wearable electronics[J]. Nanotechnology, 2018, 29(32): 325501.
[67] MAO Y Y, LI Y, XIE J Y, et al. Triboelectric nanogenerator/supercapacitor in-one self-powered textile based on PTFE yarn wrapped PDMS/MnO ₂ NW hybrid elastomer[J]. Nano Energy, 2021, 84: 105918.
[68] REN X H, XIANG X Y, YIN H F, et al. All-yarn triboelectric nanogenerator and supercapacitor based self-charging power cloth for wearable applications[J]. Nanotechnology, 2021, 32(31): 42356-42362.
[69] YANG Z T, ZHU Z T, CHEN Z X, et al. Recent advances in self-powered piezoelectric and triboelectric sensors: From material and structure design to frontier applications of artificial intelligence[J]. Sensors, 2021, 21(24): 8422.
[70] SHAO Y C, SHEN M L, ZHOU Y K, et al. Nanoge-nerator-based self-powered sensors for data collection[J]. Beilstein Journal of Nanotechnology, 2021, 12: 680-693.
[71] ZHANG W L H, XUE X Y. A self-powered wearable ultraviolet radiation detector integrated with wireless devices based on T-ZnO/PVDF composite fabric[J]. Journal of Nanoelectronics and Optoelectronics, 2021, 16(4): 515-521.
[72] SU Y D, LU L, ZHOU M. Wearable microbial fuel cells for sustainable self-powered electronic skins[J]. ACS Applied Materials & Interfaces, 2022, 14(7): 8664-8668.
[73] LIU W J, LONG Z H, YANG G Y, et al. A self-powered wearable motion sensor for monitoring volleyball skill and building big sports data[J]. Biosensors-Basel, 2022, 12(2): 60.
[74] LU Z, ZHU Y S, JIA C J, et al. A self-powered portable flexible sensor of monitoring speed skating techniques[J]. Biosensors-Basel, 2021, 11(4): 108.
[75] LI Q Y, DAI K R, ZHANG W L, et al. Triboelectric nanogenerator-based wearable electronic devices and systems: Toward informatization and intelligence[J]. Digital Signal Processing, 2021, 113: 103038.
[76] HE W Y, WANG H Y, HUANG Y X, et al. Textile-based moisture power generator with dual asymmetric structure and high flexibility for wearable applications[J]. Nano Energy, 2022, 95: 107017.
[77] LI H, SONG H, LONG M J, et al. Mortise-tenon joint structured hydrophobic surface-functionalized barium titanate/polyvinylidene fluoride nanocomposites for printed self-powered wearable sensors[J]. Nanoscale, 2021, 13(4): 2542-2555.
[78] HUANG J R, GU J F, LIU J T, et al. Environment stable ionic organohydrogel as a self-powered integrated system for wearable electronics[J]. Journal of Materials Chemistry A, 2021, 9(30): 16345-16358.
[79] GYANCHANDANI V, MASABI S N, FU H L, et al. A self-powered wearable device using the photovoltaic effect for human heath monitoring[C]// Proceedings of the 20th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications, Exeter: Electr Network. 2021: 60-63.
[80] HOU Y, YANG Y, WANG Z Y, et al. Whole fabric-assisted thermoelectric devices for wearable electronics[J]. Advanced Science, 2022, 9(1): 2103574.