en 
Wechat QRcode
Hotline:0755-22277778
Tel：0755-22277778
Mobile：13826586185（Mr.Duan）
Fax：0755-22277776
E-mail：duanlian@xianjinyuan.cn
Flexible wearable dry electrode · Long term bioelectric monitoring scheme
In the ECG examination room of the hospital, Ag/AgCl wet electrode combined with conductive gel to collect ECG signals - clear and stable, which is recognized as the clinical "gold standard". But when this standard was transplanted to wearable devices, problems began to emerge: gel would dry up over time, contact impedance would rise, and signal quality would continue to decline; The ingredients of gel may cause skin irritation or even allergy; The electrode cannot be reused and is not suitable for daily wear.
The limitations of wet electrodes are particularly prominent in scenarios that require continuous monitoring for hours or even days. What the wearable health monitoring equipment needs is an electrode that "sticks on without tubes" - no conductive gel, no stimulation, can be worn for a long time, and can be reused.
Core proposition:Flexible wearable dry electrodes are becoming the answer to this demand.
Flexible wearable electrodes are a type of bioelectric signal acquisition device based on flexible polymer materials and constructed with conductive functional layers through precision coating or composite material processes. It can maintain stable electrical properties and structural integrity under complex deformations such as bending, stretching, and folding.
A typical flexible wearable electrode consists of three parts:
PI, PET, PEN, PDMS, TPU, etc. provide mechanical support and skin adhesion.
Metal coating (gold/platinum/Ag/AgCl), carbon based material or conductive polymer, responsible for signal acquisition.
Used to further reduce contact impedance or enhance biocompatibility.
The core value of flexible dry electrodes lies in solving the three major congenital defects of wet electrodes:
The dry electrode directly contacts with the skin, does not rely on the conductive gel, and the signal quality does not decay with time.
No need for chemical gel and adhesives, reducing the risk of skin allergy and inflammation.
Can be repeatedly cleaned and reused, significantly reducing long-term usage costs.
Signal quality:The correlation between ECG signals collected by printed graphene electrodes and commercial Ag/AgCl electrodes reached 99.34%. In wearable ECG monitoring, the signal quality generated by flexible dry electrode is equivalent to that of gel electrode.
The performance of flexible wearable electrodes is rooted in the selection of their conductive materials. The current mainstream material system covers three categories: carbon based, metal based, and conductive polymers:
Ultra high conductivity and mechanical flexibility. The conductivity of CNT composite electrode is 20 S/cm, and the electrical performance degradation during deformation is minimal. The signal-to-noise ratio of laser-induced graphene electrode reaches 48.659dB.
Excellent conductivity and flexibility, the composite electrode achieves good tensile performance while maintaining high conductivity.
Gold (resistivity 2.44 μ Ω· cm), platinum (1.65 μ Ω· cm), Ag/AgCl. Gold plated electrodes have low impedance on PI substrates and are suitable for wearable applications.
Conductive polymer:PEDOT: PSS combines solution processability and biocompatibility, and can be directly patterned onto flexible substrates for electrode preparation through inkjet printing and other methods.
The stretchability of the material itself is limited. Structural design is equally crucial for maintaining stable contact between the electrode and the skin during dynamic motion.
Winding geometric design absorbs strain through in-plane deformation during stretching. The optimized negative Poisson's ratio structure can reduce tensile stress and bending stress by 67% and 71%, respectively.
Rigid components are distributed on the "island" and connected by stretchable "bridges", with deformation concentrated on the bridge structure.
PDMS, TPU, and other materials endow the electrode with intrinsic stretchability, with a stretching rate of up to 140% -300% and over 50000 bending cycles without failure.
The MWCNT-PDMS dry electrode has a resistance of approximately 490.75k Ω at 10Hz, while the graphene gold finger electrode has a resistance as low as 20.8 Ω on dry skin.
Laser induced graphene electrode at 48.659dB; optimized flexible electrode at a maximum of 34.9dB.
R3.5mm static bending resistance increases by only 5%; 100 bending resistance changes<7%; After 30000 cycles, the resistance remains stable. <>
The stretching rate is 140% -300%, and the electrical performance attenuation during deformation is minimal, with no significant drift.
| performance metrics | typical value | Reference |
|---|---|---|
| Contact impedance (10Hz) | 490.75±71.57kΩ（MWCNT-PDMS） | — |
| Low interface impedance | 20.8 Ω (graphene gold forked electrode) | — |
| Signal to Noise Ratio (SNR) | 48.659dB (laser-induced graphene); 34.9dB (optimized electrode) | — |
| elongation rate | 140% (partial materials); 300% (linear electrode) | — |
| Bending cycle | More than 50000 times without any faults | — |
| Square resistance (stretchable transparent electrode) | ~25Ω/□ | — |
The area with the highest usage. Integrated into smart watches and patches, real-time collection of signals such as ECG/EMG, combined with sweat analysis to detect glucose, lactate, etc. The global wearable medical device market size has exceeded 68 billion US dollars by 2025.
Flexible sEMG electrodes play a crucial role in rehabilitation assessment, motion monitoring, and prosthetic control, adapting to wearable forms such as wristbands and patches.
Flexible electrodes have become the core components of BCI, and the global market size of flexible neural electrodes is expected to reach 1.87 billion US dollars by 2025, with a projected breakthrough of 8.23 billion US dollars by 2030.
Electronic skin and human-computer interaction:Flexible wearable electrodes can also be integrated into electronic skin and other systems for scenarios such as human-computer interaction and emotional monitoring.
Advanced Institute (Shenzhen) Technology Co., Ltd. was established in 2016 and is a national high-tech enterprise specializing in flexible substrate coating, shielding materials, absorbing materials, and precious metal pastes. The company has independently built a magnetron sputtering and vacuum evaporation production line, using roll to roll continuous production technology, which can continuously deposit metal layers on the surface of flexible polymer films.
In response to the specific requirements of flexible wearable electrodes, Advanced Institute Technology provides the following core capabilities:
FEP, PI, PET, LCP, PPS, PEN, PP, PDMS, TPU and other elastic materials.
A full range of metal coatings including gold, silver, copper, aluminum, tin, nickel, titanium, platinum, etc.
Composite processes such as magnetron sputtering, vacuum evaporation, and pulse electroplating.
Plasma pretreatment activation, gradient coating design, cyanide free gold plating.
Nano level thickness control (several nanometers to several hundred nanometers), 5B level adhesion, ISO9001 certification.
The essence of flexible wearable electrodes is to establish a stable, low-noise, and biologically friendly signal channel between rigid electronic devices and soft biological tissues. It uses a flexible substrate to match the mechanical properties of the skin, a low impedance conductive layer to ensure signal quality, and a structural design to "guide" motion strain from the functional layer - the three work together to answer a core engineering question: how to make electronic devices as soft as skin while also understanding the body's language.
From electrocardiogram monitoring to brain computer interfaces, from exercise rehabilitation to human-computer interaction - flexible wearable electrodes are bringing the collection of bioelectric signals from hospitals to homes, from static to dynamic, and from "sticking up" to "growing up". In this technological evolution, material selection, structural design, and precision coating processes have always been the core variables that determine the upper limit of electrode performance.
www.avanzado.cn
© 2026 Xianjin Yuan · Flexible Wearable Dry Electrode Technology Reference
Advanced Institute (Shenzhen) Technology Co., Ltd， © two thousand and twenty-onewww.xianjinyuan.cn. All Rights Reserved.Guangdong ICP No. 2021051947 sitemap
Español
Français
Português