In-situ electrode observation as an optical sensing method for battery state of charge

Electrochromic Effect of Indium Tin Oxide in Lithium Iron Phosphate Battery Cathodes for State-of-Charge Determination

“…Apart from the chosen geometry, a more regular geometry could be investigated as well, where ITO-coated glass has to be used as an electrode current collector instead of aluminum. 17 Finally, various other electrode arrangements are possible, which have been discussed previously. 18 2.3.…”

“…Our approach of replacing carbon with ITO was presented in a previous publication. 17 There, we focused on potential applications of the correlation between the transferred electrical charge and optical reflectivity of the electrode. Because a commercial cell will not be covered with an optical window, we already proposed the use of an optical fiber embedded in a regular LFP cathode and covered with an LFP/ITO mixture to measure a light signal, which depends on the charge transferred into and from the battery.…”

Investigation of charge carrier dynamics in positive lithium-ion battery electrodes via optical in situ observation

“…We further report primarily on antimony tin oxide (ATO) nanopowder as an electrode additive to enhance the optical observability of the LFP cathode due to the replacement of the usual carbon (C) nanopowder as conductive agent. Overall, ATO behaves similar to indium tin oxide (ITO), which we used previously [28][29][30], but offers some advantages as discussed later on. For this reason, the estimation of the apparent diffusion coefficient is discussed in details only for the LFP/ATO cathode in the present manuscript.…”

Visualizing Battery Reactions and Processes by Using In Situ and In Operando Microscopies

“…This pioneering work and battery design has been adopted for other battery systems, such as aqueous batteries. 76 A typical planar cell design is shown schematically in Figure 5A. 77 By using a cylindrical battery design and imaging from the side, Sun et al 78 successfully visualized soluble polysulfide formation in a Li-sulfur (Li-S) battery.…”

“…Markers and sensors have been developed to relate optical imaging contrast with material properties. Roscher et al 76 developed a method of probing the state of charge of a LiFePO 4 cathode precisely by adding transparent conductive oxides (electrochromic ITO) as a marker. This is an interesting direction to pursue because it expands what can be visualized.…”