How to test tens of thousands of electrochemical formulations? Ou Shisheng builds a standardized data pipeline for high-throughput electrochemical liquid preparation.
Sixty solid powders and sixty liquid reagents can create 3,600 unique pairings. When each pairing is tested at three different concentration levels, the total number of test solutions rises to 10,800. This calculation merely illustrates a 60x60 matrix; actual electrolyte formulations involve many more variables, creating an exponentially larger number of possible combinations. If preparing each solution manually takes an estimated 6 minutes, this single batch would require approximately 1,080 hours, or 135 working days, before any actual testing even begins.
The main obstacle to high-throughput electrochemical experiments is the repetitive and labor-intensive process of dispensing liquids. The Ou Shisheng automated integrated electrochemical test platform streamlines this by combining solid dosing, liquid transfer, solvent measurement, shaking and dissolving, 8-channel sample delivery, and cleaning and waste disposal into a continuous workflow. Modules can be easily customized to meet specific experimental needs. The number of channels can be adjusted to achieve the desired throughput and single-line flow rate. All operation logs and experimental reports are fully saved within the unified software platform.
This platform can prepare multi-component electrolytes, conduct formulation concentration gradient tests, perform sample pretreatment for parallel catalyst evaluation, and execute repeatability experiments that require cross-batch comparisons. For research groups that already have electrochemical workstations and test cells, this platform can be integrated to add automatic liquid preparation and sample delivery capabilities, while still utilizing their existing testing hardware.
Figure 1 | Ou Shisheng Automated Integrated Electrochemical Experimental Platform
01 One Platform for Liquid Preparation and Sample Delivery Before Testing
The platform features a floor-standing, integrated design. The upper section houses the liquid preparation and testing areas, while the lower frame contains the electrical control cabinet and space for electrochemical workstations. Internally, the system is functionally divided into a liquid preparation unit, a test unit, and a motion module.
The liquid preparation unit includes 60 x 20 mL bottles for liquid storage and 60 x 15 mL hoppers for solid feeding. Software-based consumable management and low-material alerts enable the continuous execution of tens of thousands of tasks in batches. Material can be replenished during operation without interrupting the workflow. A 6-axis robotic arm, equipped with a quick-change gripper, switches end effectors for handling bottles, capping/uncapping, dispensing solids, and transferring liquids. The test unit features 8 syringe pumps with independent flow paths, f. An XYZ three-axis motion module positions the inlet tubing. Starting from the reagent rack, materials are formulated, dissolved, and delivered to the test cell. Waste liquid is directed to a collection point. This system addresses the challenges of maintaining consistent conditions and eliminating manual bias during the repeated preparation of large batches of micro-scale formulation samples.
Figure 2 | Top down rendering of the platform: reagent zone, robotic arm, liquid preparation zone and test zone are integrated within one frame
02 From Reagent Vial to Test Cell: Workflow of One Experimental Cycle
Solid raw materials are weighed according to the formulation. The robotic arm picks an empty vial and places it on the dosing balance. It then accesses the corresponding solid hopper for feeding. The solid dosing range is 5–2000 mg, with a balance readability of 0.1 mg and an accuracy of ±0.3 mg at the 20 mg dosing point. Weighing results are directly integrated into the dosing process control, eliminating any gaps that occur with manual weighing, transfer, and logging.
Liquid components are dispensed by the liquid-handling module. The robot switches to a pipette tool for aspiration. The system utilizes disposable tips and includes features for tip presence detection, automatic tip ejection, liquid level sensing, and tip clogging detection. Any abnormalities during pipetting are captured and logged to prevent subsequent actions when tips are missing or insufficient liquid is detected.
Solvent volumetric addition and shaking dissolution proceed sequentially. The syringe pump connects to different solvents via a 6-port switching valve. The line is flushed first, and then solvent is dispensed at the target volume. The volumetric error is less than 1%, with a repeatability of RSD less than 0.5%. The vial is then transferred to the shaker, which has an adjustable speed range of 30–300 rpm and a speed tolerance of ±2%, ensuring consistent dissolution conditions across all samples.
The prepared solution is delivered to an 8-channel test zone. The test unit features 8 syringe pumps with a flow range of 0.1–30 mL/min. An XYZ three-axis motion module positions the inlet tubing for sample aspiration, and the 8 outlet lines are routed to individual test cells. Users can reuse their existing test cells and electrochemical workstations, as the platform provides reserved mounting space on the lower frame and a perforated panel.
Following sample testing, the flow paths are automatically cleaned, and waste is discharged separately. The system first cleans the exterior of the inlet tubing and needles before purging the outlet lines. The 8 outlet streams converge through check valves, and an automatic three-way valve directs aqueous and organic waste into separate collection containers. A scheduler coordinates cleaning, sample delivery, and the next formulation run, eliminating manual tracking steps during continuous experiments.
03 Three Special Designs Tailored for Electrochemical Experiments
1. Metal-Free Wetted Parts Throughout the Fluid Path
Electrochemical systems are highly sensitive to even trace amounts of metal contaminants. Ions like iron (Fe), copper (Cu), and nickel (Ni) can deposit onto electrode surfaces, which can alter apparent activity and product selectivity, thereby complicating comparisons between different formulations. To prevent this, the platform adheres to a strict metal-free specification for all wetted parts. This includes using borosilicate glass and ceramic for syringe pump barrels and needles, PTFE for seals and valve spools, PEEK for fittings and structural components, and PP/PFA tubing.
This material selection achieves a balance between chemical inertness, effective sealing, and mechanical strength, preventing metal ions from leaching out of the hardware and into the solutions. For applications such as electrolyte screening, electrocatalytic evaluation, and other tests that require the comparison of subtle responses, this design is essential for ensuring reliable interpretation of data across different experimental groups.
2. Independent Error Control for Solids, Liquids, and Solvents
Instead of grouping all operations under a single "automated dispensing" function, the platform uses separate metering units for the three types of feed. Solids are controlled in a closed-loop system by a balance and dosing mechanism. Liquid components are handled by the liquid-handling module, and solvents are metered by syringe pump stroke and a volumetric flow circuit. Each step has verifiable specifications, allowing for the assessment of preparation bias against experimental requirements.
These parameters influence electrochemical test results. Shifts in concentration can affect limiting diffusion current, solution conductivity, and product quantification. Therefore, dispensing accuracy is important not only for operational convenience but also for making valid comparisons of curves across different batches. By replacing manual weighing, pipetting, and volumetric additions with controlled automated actions, the platform ensures consistent preparation conditions for high-throughput screening.
3. 8 Independent Sample Delivery Channels with Dedicated Cleaning and Waste Routing
During continuous testing, carryover from a previous sample can contaminate the next one. The platform prevents cross-contamination through an optimized flushing sequence. First, the inlet tubing, which carries the highest contamination risk due to sequential vial aspiration, is cleaned. This is followed by cleaning the outlet lines. The 8 pump bodies and inlet lines operate independently and only converge downstream. Check valves prevent backflow of waste liquid. Aqueous and organic waste streams are routed to separate collection lines.
Parallel 8-channel operation also supports in-batch control experiments. All samples are prepared by the same dispensing unit and measured within a narrow time window. This minimizes bias from solvent replacement, environmental drift, and instrument drift, ensuring reliable inter-group comparisons. For formulation ranking campaigns, this capability offers greater value than simply increasing the number of assays per run.
4. Software unifies workflow, resource management and experimental records
The platform supports wizard guided operation and custom workflow creation. Users can build run sequences based on formulations and test procedures. The scheduler handles parallel multitasking; jobs can be paused, resumed and exported. Manual and automatic dual modes support switching between commissioning and formal runs, while role based access control enables multi user sharing.
A 360° overhead camera monitors system status during operation. The software automatically generates run logs. The resource management module tracks consumables and reagents centrally and displays low stock alerts. After completion, the analytics module generates test reports. Liquid preparation, sample delivery, cleaning and exception events are logged in one unified record.
Process metadata such as actual weighed mass, solvent vial position, flush cycles, shaker speed and duration can be exported as structured data fields and archived together with electrochemical curves. For formulation screening or activity prediction, the model can access not only final test results but also preparation conditions to interpret batch to batch variation.
The automated integrated electrochemical experimental platform goes beyond simply automating manual liquid preparation. It transforms preparation conditions and operational sequences into controllable, traceable, and standardized variables. In the rapidly advancing field of AI-driven electrochemical research, high-quality, comparable experimental data is crucial for formulation screening and predicting catalyst activity. Beginning with sample preparation, this platform establishes a robust experimental infrastructure for electrochemical research within the AI4S paradigm.
