Exploring Ba_xCoO₂ as a potential cathode material for rechargeable batteries

Abstract

Layered cobalt oxides are emerging as a pivotal class of cathode materials due to their high theoretical energy density, tunable interlayer spacing for efficient ion diffusion, and structural resilience under electrochemical cycling. Here, we report the synthesis of barium cobaltite (Ba_xCoO₂, x ≈ 0.34) through a two-step solid-state reaction coupled with ion exchange, establishing a stable layered structure consisting of alternating Ba−O layers and edge-shared CoO₆ octahedral sheets. This unique architecture provides an expanded interlayer spacing (c-axis: 1.23 nm) and efficient Li⁺ diffusion channels, enabling a lithium-ion battery (LIB) with the Ba_xCoO₂ cathode to achieve ultrahigh reversible capacities of 820.7 mAh·g⁻¹ at 0.1C and 483.2 mAh·g⁻¹ at 5C, along with 99.37% Coulombic efficiency retained over 1000 cycles, demonstrating remarkable cycling stability. Comparative studies on a sodium-ion battery (SIB) also reveal the superior capacity of the LIB, attributed to smaller ionic radius of Li⁺ and stabilized electrode–electrolyte interface. These results demonstrate that the combination of structural resilience and fast ion kinetics position Ba_xCoO₂ as a promising candidate for high-energy-density storage systems. Further optimization of the Ba/Co ratio and defect engineering may unlock enhanced cyclability for practical applications.

Graphical abstract

Keywords

rechargeable battery / cathode material / layered cobalt oxide / barium cobaltite / lithium-ion battery / sodium-ion battery

References

[1] Blomgren G E . The development and future of lithium ion batteries.Journal of the Electrochemical Society, 2017, 164(1): A5019

[2] Chen T X, Lai X, Chen F, . Empowering lithium-ion battery manufacturing with big data: current status, challenges, and future.Journal of Power Sources, 2024, 623: 235400

[3] Wang T, Ren K, He M, . Synthesis and manipulation of single-crystalline lithium nickel manganese cobalt oxide cathodes: a review of growth mechanism.Frontiers in Chemistry, 2020, 8: 747

[4] Manthiram A, Goodenough J B . Layered lithium cobalt oxide cathodes.Nature Energy, 2021, 6: 323

[5] Li Y J, Dong L P, Shi P, . Selective recovery of lithium from lithium iron phosphate.Journal of Power Sources, 2024, 598: 234158

[6] Chen S, Zhang X, Xia M, . Issues and challenges of layered lithium nickel cobalt manganese oxides for lithium-ion batteries.Journal of Electroanalytical Chemistry, 2021, 895: 115412

[7] Billaud J, Bouville F, Magrini T, . Magnetically aligned graphite electrodes for high-rate performance Li-ion batteries.Nature Energy, 2016, 1: 16097

[8] Yang D, You D, BingnanDeng , . Lithium titanate modified separators for long cycling life lithium metal anode.Ionics, 2023, 29(12): 5161–5168

[9] Deng C, Li X, Chen R, . Recent advances in rocking chair batteries and beyond.Energy Storage Materials, 2023, 60: 102820

[10] Zhang C, Chou S, Guo Z, . Beyond lithium-ion batteries.Advanced Functional Materials, 2024, 34(5): 2308001

[11] Masias A, Marcicki J, Paxton W A . Opportunities and challenges of lithium ion batteries in automotive applications.ACS Energy Letters, 2021, 6(2): 621–630

[12] Nwanna E C, Bitire S, Imoisili P E, . An overview of the application of atomic layer deposition process for lithium-ion based batteries.International Journal of Energy Research, 2022, 46(8): 10499–10521

[13] Xu B, Lee J, Kwon D, . Mitigation strategies for Li-ion battery thermal runaway: a review.Renewable & Sustainable Energy Reviews, 2021, 150: 111437

[14] Zheng Y S, Che Y H, Hu X S, . Thermal state monitoring of lithium-ion batteries: progress, challenges, and opportunities.Progress in Energy and Combustion Science, 2024, 100: 101120

[15] Xie H G, Peng H R, Jiang D T, . Structures, issues, and optimization strategies of Ni-rich and Co-low cathode materials for lithium-ion battery.Chemical Engineering Journal, 2023, 470: 144051

[16] Sahadevan J, Sanjay R, Muthu S E, . Investigation on structural, morphological and magnetic properties of barium cobaltite (BaCoO₃) nanoparticle.Materials Science and Engineering: B, 2023, 296: 116669

[17] Zhang X, Zhang Y Q, Wu L, . Ba_1/3CoO₂: a thermoelectric oxide showing a reliable ZT of ~0.55 at 600 °C in air.ACS Applied Materials & Interfaces, 2022, 14(29): 33355–33360

[18] Zhang Y Q, Ohta H . Recent progress in thermoelectric layered cobalt oxide thin films.NPG Asia Materials, 2023, 15: 67

[19] Diatta A, Colin C V, Viennois R, . BaCoO₂ with tetrahedral cobalt coordination: the missing element to understand energy storage and conversion applications in BaCoO_3−δ-based materials.Journal of the American Chemical Society, 2024, 146(22): 15027–15035

[20] Iqbal Waidha A, Siddiqui H K, Ikeda Y, . Structural, magnetic and catalytic properties of a new vacancy ordered perovskite type barium cobaltate BaCoO_2.67.Chemistry: A European Journal, 2021, 27(38): 9763–9767

[21] Cho H J, Takashima Y, Nezu Y, . Anisotropic heat conduction in ion-substituted layered cobalt oxides.Advanced Materials Interfaces, 2020, 7(3): 1901816

[22] Knížek K, Hejtmánek J, Maryško M, . Structure and properties of a novel cobaltate La_0.30CoO₂.Journal of Solid State Chemistry, 2011, 184(8): 2231–2237

[23] Kang K, Kato F, Nakano A, . Fabrication and thermoelectric properties of freestanding Ba_1/3CoO₂ single-crystalline films.ACS Applied Electronic Materials, 2023, 5(10): 5749–5754

[24] Takashima Y, Zhang Y, Wei J, . Layered cobalt oxide epitaxial films exhibiting thermoelectric ZT = 0.11 at room temperature.Journal of Materials Chemistry A: Materials for Energy and Sustainability, 2021, 9(1): 274–280

[25] Cushing B L, Wiley J B . Topotactic routes to layered calcium cobalt oxides.Journal of Solid State Chemistry, 1998, 141(2): 385–391

[26] Ishikawa R, Ono Y, Miyazaki Y, . Low-temperature synthesis and electric properties of new layered cobaltite, Sr_xCoO₂.Japanese Journal of Applied Physics, 2002, 41(Part 2): L337–L339

[27] Liu J, Huang X, Yang D, . Synthesis and physical properties of layered Ba_xCoO₂.Dalton Transactions, 2014, 43(41): 15414–15418

[28] Zhang J, Meng D C, Huang H L, . Phase competition in the growth of SrCoO_x/LaAlO₃ thin films.AIP Advances, 2018, 8: 025322

[29] Mathiyalagan K, Ponnaiah A, Karuppiah K, . Enhanced performance on layered O3-Na_0.95CrO₂ cathode material for emerging sodium-ion batteries.Ionics, 2020, 26: 3929–3936

[30] Julien C, Mauger A, Zaghib K, . Optimization of layered cathode materials for lithium-ion batteries.Materials, 2016, 9(7): 595

[31] Phogat P, Dey S, Wan M . Comprehensive review of sodium-ion batteries: principles, materials, performance, challenges, and future perspectives.Materials Science and Engineering: B, 2025, 312: 117870

[32] Suntharam N M, Bashir S, Vengadaesvaran B, . Fundamentals and key components of sodium-ion batteries: challenges and future perspectives.Materials Today: Chemistry, 2024, 42: 102350

[33] Idriss H . On the wrong assignment of the XPS O 1s signal at 531–532 eV attributed to oxygen vacancies in photo- and electro-catalysts for water splitting and other materials applications.Surface Science, 2021, 712: 121894

[34] Ouyang D X, Liu B, Huang J, . Degradation and safety performance of lithium-ion cells under high-rate charging/discharging scenarios.Process Safety and Environmental Protection, 2024, 185: 76–85

[35] Wang R X, Zhou X, Wang Y, . Degradation analysis of lithium-ion batteries under ultrahigh-rate discharge profile.Applied Energy, 2024, 376(A): 124241

[36] Weiss M, Ruess R, Kasnatscheew J, . Fast charging of lithium-ion batteries: a review of materials aspects.Advanced Energy Materials, 2021, 11(33): 2101126

[37] Xie W L, Guo P, Gao X L . Elucidating the rate limitation of lithium-ion batteries under different charging conditions through polarization analysis.Journal of Energy Storage, 2024, 82: 110554

[38] Meng X, Wang J L, Li L . Layered-oxide cathode materials for fast-charging lithium-ion batteries: a review.Molecules, 2023, 28(10): 4007

[39] Nayak P K, Yang L T, Brehm W, . From lithium-ion to sodium-ion batteries: advantages, challenges, and surprises.Angewandte Chemie International Edition, 2018, 57(1): 102–120

RIGHTS & PERMISSIONS

Higher Education Press