Laboratory of Electrochemical Technologies – Batteries and Supercapacitors

Laboratory of Electrochemical Technologies – Batteries and Supercapacitors

The laboratory is a research unit whose members include scientists from the Institute of Physical Chemistry, the Institute of Electrochemistry and Energy Systems and the Institute of General and Inorganic Chemistry of the Bulgarian Academy of Sciences (BAS). It carries out fundamental and applied research, applying modern approaches to the electrochemical synthesis, electrochemical characterisation and testing of materials for electrocatalytic applications and of materials used for electrochemical energy storage. Its activities also focus on the physicochemical testing of materials for electrochemical energy storage/conversion systems, mainly for lithium-ion batteries, post-lithium-ion batteries and supercapacitors. Potential partners and clients of the laboratory may include academic and industrial teams in Bulgaria and abroad with similar research interests, as well as companies engaged in applied work in the above fields.

Description of Activities

  • Study of electrolytic and/or electroless deposition of metal particles on various types of screen-printed electrodes with a view to obtaining materials with high catalytic activity, suitable for use as electrochemical sensor materials.
  • Electrochemical study of the properties of electrodes coated with modified nanomaterials for electrocatalytic and photoelectrocatalytic purposes.
  • Study of the absorption behaviour in the ultraviolet and visible regions of electrodes coated with conducting polymers, including after their use for electrocatalytic purposes.
  • Spectroelectrochemical study of solutions used for electrocatalytic purposes.
  • Recording of current–voltage dependences of electrodes with various architectures and configurations using a wide range of electrochemical techniques and methods;
  • Electrochemical characterisation of new laboratory- or industrially produced electrode materials and systems for energy generation and storage;
  • Optimisation of the electrochemical and electrical parameters of existing commercial products;
  • Quantitative and qualitative relationships between the chemical structure and microstructure of electrode materials and their electrochemical activity;
  • Ex-situ and in-situ study of the mechanisms and elementary processes of electrochemical reactions and of the intermediate products formed during their course;
  • Development of new methods for the standardised determination of the electrochemical and electrical parameters of electrode materials and systems for energy generation and storage;
  • Short-term and long-term testing of electrode materials and systems for energy generation and storage in accordance with established international standards and algorithms;
  • External quality control for the electrochemical industry (electrochemical characterisation of raw materials, intermediate and final products);
  • Electrochemical studies in potentiostatic and galvanostatic mode: determination of specific capacity, capacity stability during prolonged cycling, and capacity stability at different current densities

Service Description

• Spectroelectrochemical measurements of electroactive electrode coatings.
• Spectroelectrochemical measurements of solutions.
• Measurement of the electrochemical properties and cycling stability of cathode and anode electrode materials for batteries, supercapacitors, fuel cells and electrolysers.
• Determination of the electrochemical activity of photosensitive materials and study of electrocatalytic properties with an induced photoeffect.
• Electrochemical characterisation of the electrode/electrolyte interface by electrochemical quartz crystal microbalance measurements.
• Study of the course of electrochemical reactions and of changes in the starting, intermediate and final products of the reactions under study, using rotating ring-disc and disc electrodes.
• Assembly of model two- and three-electrode cells for testing positive and/or negative electrode materials in the presence of non-aqueous electrolytes (including ionic liquids), in a glovebox under an argon atmosphere with controlled humidity and oxygen levels. Cells with aqueous electrolytes can also be constructed.
• Preparation of non-aqueous electrolyte solutions based on organic solvents.
• Microscopic inspection of changes in the surface of electrode materials, with the option of imaging the sample.
• Preparation of moisture-sensitive samples for subsequent ex-situ analyses.
• Measurement of basic electrochemical parameters and characteristics such as cyclic voltammograms, current–voltage characteristics, impedance spectra, pulse measurements, etc., in both potentiostatic and galvanostatic mode.

Equipment

SPECTROELECTROCHEMICAL EQUIPMENT
Capability for simultaneous measurement of electrical signals (current or potential) and spectrometry in the visible and ultraviolet regions.
• Potentiostat/galvanostat (Autolab) for applying/measuring electrical signals, with a total electrical power of 1 kW
• Light source in the visible and ultraviolet regions (200–1100 nm)
• Spectrometer
• Optical fibres
• Quartz cuvette/electrochemical cell for transmitted light
• Teflon cells for transmitted and reflected light, operating with screen-printed electrodes (working electrodes of carbon, gold, silver, ITO, PEDOT, SWCNT)

Front panel of an AUTOLAB potentiostat with display reading 1.37 V and 0.00 µA, with cables plugged in

Spectroelectrochemical equipment
• Screen-printed electrodes
• Teflon cell operating with screen-printed electrodes

Diagram of a printed electrode with the working, reference and auxiliary electrodes and their contacts labelled

PHOTOELECTROCHEMICAL STATION
• Gamry Interface 5000 E and Interface 1000E potentiostats operating in synchrony
• Applied current up to ±5 A and potential ±11 V, with high resolution and accuracy
• Electrochemical impedance measurement with a maximum frequency of up to 2 MHz at a signal amplitude of up to 3 V and 5 A
• Photoelectrochemical measurement stand with a protective, optically isolated cage, UV and white light sources with a frequency of up to 1 MHz, and a photodetector

Photoelectrochemical station

Laboratory table with two Gamry potentiostats, a Thorlabs optical bench with lens holders, and cables

POTENTIOSTAT/GALVANOSTAT SYSTEM WITH IMPEDANCE ANALYSER AND MICROBALANCE
• Gamry Reference 3000 AE potentiostat and Reference 30k current booster for connecting an electrochemical cell operating with two, three or four electrodes, and small batteries
• Applied current from the potentiostat up to ±3 A and potential ±32 V, with high resolution and accuracy, plus 8 voltage measurement channels. Boosting of the applied current up to ±30 A and voltage from -2 V to 20 V
• Electrochemical impedance measurement with a maximum frequency of up to 1 MHz at a signal amplitude of up to 3 V and 3 A
• Gamry eQCM 10M quartz crystal microbalance, with a maximum resonator frequency of up to 10 MHz and a measurable change in electrode sample mass down to 1 ng/cm² during various types of electrochemical polarisation
• Suitable electrochemical cell with a thermostatic jacket

Potentiostat/galvanostat system with impedance analyser and microbalance

Two Gamry Reference 3000 instruments stacked and connected by cables to a metal measuring cell

BIPOTENTIOSTAT WITH ROTATING DISC ELECTRODE (RDE) AND ROTATING RING-DISC ELECTRODE (RRDE)
• Gamry Reference 600+ bipotentiostat for simultaneous measurement on two working electrodes and for connecting an electrochemical cell operating with two, three, four or five electrodes
• Applied current up to 0.6 A and potential ±11 V, with high resolution and accuracy, and a minimum signal acquisition time down to 5 µs
• Electrochemical impedance measurement with a maximum frequency of up to 5 MHz at a signal amplitude of up to 3 V and 0.6 A
• Measurement stand for rotating disc and ring-disc electrodes, with a rotator of up to 10 000 rpm and associated accessories

Bipotentiostat with rotating disc electrode (RDE) and rotating ring-disc electrode (RRDE)

Glass electrochemical cell with a rotating electrode and Gamry control modules on a workbench

GLOVEBOX MBraun, MB-Unilab Pro SP (1500/780)
• H2O and O2 content < 0.1 ppm
• The equipment enables moisture-sensitive samples to be handled and prepared for analysis in an argon atmosphere with controlled moisture and oxygen levels

MBraun glovebox

Illuminated laboratory chamber with a microscope, black extraction hose and a laptop showing an image of a sample

Additional glovebox equipment: Zeiss Stemi 508 microscope
• The microscope allows both direct assessment of the condition of the samples and image capture

Zeiss Stemi 508 microscope

MULTICHANNEL POTENTIOSTAT/GALVANOSTAT AND IMPEDANCE ANALYSER Biologic VMP-3e
• 32 independent channels for potentiostatic/galvanostatic measurements, with a voltage range from -20 V to +20 V and a current range from 20 nA to 1 A
• Capability for electrochemical impedance spectroscopy studies in the frequency range from 10 μHz to 1 MHz

Biologic VMP-3e multichannel potentiostat/galvanostat and impedance analyser

 

Blue laboratory apparatus with tubes and coloured connectors, linked to a computer and a monitor showing graphs
Zeiss stereo microscope in a transparent chamber with glove ports, with a shelf of reagents behind

Access to the Laboratory of Electrochemical Technologies

The Laboratory of Electrochemical Technologies is part of the research infrastructure of the National Centre of Excellence “Mechatronics and Clean Technologies” and is located on the Geo Milev campus. Requests for access and for joint research are therefore handled centrally — see Contacts. A full overview of the Centre’s other laboratories is also available on the Infrastructure and Laboratories page.

The electrochemical technologies equipment was established under project BG16RFPR002-1.014-0006, funded by the Programme “Research, Innovation and Digitalisation for Smart Transformation” 2021–2027, co-financed by the European Union through the European Regional Development Fund.