ML for electrolysis life cycle testing

[sgbaird]

Some initial discussions

https://www.youtube.com/watch?v=6VVL-J28gtU

[sgbaird]

@programlich

[sgbaird]

Maybe something interesting here once it processes:

https://hasanyone.com/?id=53ee7bc7

EDIT (response below):

NO, not as far as we can tell

Reasoning

Based on the relevant papers I have examined, there is no evidence of life cycle analysis or accelerated stress tests specifically for nickel foam electrodes in concentrated KOH electrolysis and their effect on overpotential over time. While several studies have conducted stability tests on nickel foam-based electrodes for water splitting or ammonia oxidation, these tests do not constitute full life cycle analyses or accelerated stress tests in concentrated KOH. The stability tests reported typically involve chronoamperometry, cyclic voltammetry, or chronopotentiometry for durations ranging from 12 to 24 hours (Wang2021Ni(II)Ni(III) pages 4-5, Illathvalappil2020Hierarchical pages 16-19, Zhang2020Hydrolysis pages 15-19). These tests were often conducted in 1 M KOH or 0.1 M KOH solutions, which are not considered concentrated KOH (Illathvalappil2020Hierarchical pages 14-16, Wang2021Ni(II)Ni(III) pages 5-7). Furthermore, while some studies examined changes in electrode morphology and composition after testing, they did not specifically focus on the long-term effects on overpotential for nickel foam electrodes in concentrated KOH (Illathvalappil2020Hierarchical pages 16-19, Zhang2020Hydrolysis pages 19-24). The research appears to be more focused on evaluating the stability and performance of various catalyst materials deposited on nickel foam rather than the nickel foam substrate itself in concentrated KOH conditions.

Information may be wrong, verify before use.

(Wang2021Ni(II) Ni(III) ): Renyu Wang, Huijuan Liu, Kai Zhang, Gong Zhang, Huachun Lan, and Jiuhui Qu. Ni(ii)/ni(iii) redox couple endows ni foam-supported ni2p with excellent capability for direct ammonia oxidation. Chemical Engineering Journal, 404:126795, January 2021. doi:10.1016/j.cej.2020.126795. This article has 86 citations and is from a highest quality peer-reviewed journal. http://dx.doi.org/10.1016/j.cej.2020.126795 (Illathvalappil2020Hierarchical) Rajith Illathvalappil, Priyanka S. Walko, Fayis Kanheerampockil, Suresh K. Bhat, R. Nandini Devi, and Sreekumar Kurungot. Hierarchical nanoflower arrays of co9s8‐ni3s2 on nickel foam: a highly efficient binder‐free electrocatalyst for overall water splitting. Chemistry – A European Journal, 26(35):7900–7911, May 2020. doi:10.1002/chem.202000839. This article has 25 citations. http://dx.doi.org/10.1002/chem.202000839 (Zhang2020Hydrolysis) Ruizhi Zhang, Zhaoqiang Zhu, Jiahao Lin, Kefu Zhang, Nan Li, and Chongjun Zhao. Hydrolysis assisted in-situ growth of 3d hierarchical fes/nis/nickel foam electrode for overall water splitting. Electrochimica Acta, 332:135534, February 2020. doi:10.1016/j.electacta.2019.135534. This article has 47 citations and is from a domain leading peer-reviewed journal. http://dx.doi.org/10.1016/j.electacta.2019.135534

Stats

Tokens Used - 47,734 cost - $0.19 duration 200.49 - seconds references considered - 7 references cited in answer - 5

[sgbaird]

Likewise:

https://hasanyone.com/?id=33ee89fc

EDIT:

Response: YES

Reasoning

Researchers have studied how to accelerate the degradation of working electrodes for electrolysis applications. Multiple studies have explored accelerated durability testing (ADT) and accelerated stress testing (AST) protocols for various electrolysis systems.

• CO₂ Electrolysis: Researchers have investigated methods to accelerate cathode degradation by increasing current density, electrolyte concentration, and operating temperature (Nwabara2020Towards, pp. 10-13). They found that higher current densities and electrolyte concentrations led to faster degradation of silver cathodes, as measured by decreases in CO faradaic efficiency.

• Water Electrolysis: Accelerated stress testing has been used to study catalyst degradation under different operating conditions (Nwabara2020Towards, pp. 5-6).

• Solid Oxide Electrolysis Cells: Experiments have been conducted using high steam partial pressures, fast load changes, and high voltages to induce and accelerate specific degradation phenomena (Königshofer2021Development, pp. 1-2).

• Chlor-Alkali Electrolysis: Researchers have manipulated factors such as temperature, current density, and electrolyte concentration to speed up electrode deterioration (Nwabara2020Towards, pp. 5-7).

Note: Information may be incorrect; please verify before use.

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References

• Nwabara2020Towards:
  U. O. Nwabara, M. P. de Heer, E. R. Cofell, S. Verma, E. Negro, and Paul J. A. Kenis. "Towards accelerated durability testing protocols for CO₂ electrolysis." Journal of Materials Chemistry A, 8(43):22557–22571, 2020. doi:10.1039/d0ta08695a. This article has 31 citations.

• Königshofer2021Development:
  Benjamin Königshofer, Gernot Pongratz, Gjorgji Nusev, Pavle Boškoski, Michael Höber, Đani Juričić, Mihails Kusnezoff, Nikolai Trofimenko, Hartmuth Schröttner, Christoph Hochenauer, and Vanja Subotić. "Development of test protocols for solid oxide electrolysis cells operated under accelerated degradation conditions." Journal of Power Sources, 497:229875, June 2021. doi:10.1016/j.jpowsour.2021.229875. This article has 18 citations.

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Stats

• Tokens Used: 45,500
• Cost: $0.18
• Duration: 93.14 seconds
• References Considered: 7
• References Cited: 6

[programlich]

Pretty cool! Haven't heared about this service before.

I think the first point is interesting, because it leaves a lot of room for filling this research gap. Regarding the second question, there are probably quite a few AST protocols out there (however, most of them for experiments on cell level, rather then in basic 3 electrode setup, if I'm informed correctly). However in our case, we might be able to create an AST protocol, which not only accelerates the aging of the electrode but also gives insight into the kinds of stress parameters, which are particularly bad for our specific material. This will hopefully provide insight into the degradation mechanism(s) occuring in Raney-Ni coated Ni meshes.

[programlich]

Design Variables and Constraints

• Current density $-2A/cm²<j<0 A/cm²$
• Cycle time $1s < t_c < 12h$

Note: A current densitiy of 0 A/cm² is equivalent of OCP. The potentiostat will not actively set a current of 0A

Target Parameters

The arrow indicates if the parameter should be maximized or minimized within this experiment (with the overall goal of degrading the electrode)

• Overpotential $\eta \uparrow$
• Tafel slope $b \uparrow$
• Exchange current density $j_{0} \downarrow$
• Double layer capacity $C_{dl} \downarrow$

General Design of all measurements

1. Preconditioning (1h)
2. Stress phase (12h)
3. Analysis phase (2h)

Preconditioning

• Goal: Bring the sample into a given electrochemical state before initializing the actual stress phase
• Suggestion: Hold the electrode at -30mV for 1h

Stress phase

• Goal: Degrade the sample as fast and severe as possible
• How: Apply a $j(t)$ profile over 12h. The current density and the time over which this current density is applied will be defined by the Algorithm

Analysis phase

• Goal: Characterize the sample by measuring electrochemical key values
  1. Galvanostatic (chronoamperometric) step: 30min at -0.5 A/cm²
  2. Tafel Analysis: Creation of a Tafel plot through multiple galvanostatic steps at current densities $-1A/cm² < j < -0.001 A/cm²$ and subsequent calculation of the Tafel parameters $b$ and $j0$
  3. Double layer capacity via cyclovoltammetry as explained by 2013McCrory

[sgbaird]

Part II (a) https://youtu.be/HyBDDhy_0nQ

Part II (b) https://youtu.be/vhXEI5bqvus