Data: Failure Mode and Degradation Analysis of a Commercial Sodium-Ion Battery With Severe Gassing Issue

Sodium-ion batteries offer a promising alternative to lithium-ion batteries by addressing ecological and economic challenges. However, to assess the applicability of these cells for different sectors, understanding aging behavior, including degradation modes, is crucial. This work presents a comprehensive aging analysis of 67 commercial sodium-ion batteries under various temperatures, C-rates, and depths of discharge. We analyzed the initial cell-to-cell variance and the aging trajectories regarding capacity fade and resistance increase. We demonstrated that the cycling rate does not significantly influence the aging trajectories, whereas smaller depths of discharge significantly reduce degradation. The degradation gradients for 25 °C and 40 °C were similar; for −10 °C, we observed rapid capacity fading that can be attributed to irreversible sodium plating. Furthermore, we identified the degradation modes for four different aging categories. Since some aging tests stopped due to gas-induced current interrupt device triggering at low current rates and states of charge, we proposed two hypotheses for the gassing under specific conditions, suggesting inadequate gas consumption in cathode-electrolyte side reactions or solid electrolyte interphase instability as potential causes. Overall, this work provides a valuable in-depth analysis of the aging behavior of a commercial sodium-ion battery as a function of temperature, C-rate, and depth of discharge, with data made available for further research.

钠离子电池（Sodium-ion Batteries）可作为锂离子电池（Lithium-ion Batteries）极具前景的替代方案，能够解决后者在生态与经济层面的挑战。然而，若要评估此类电池在不同应用场景中的适用性，明晰其老化行为（Aging Behavior），包括降解模式（Degradation Modes），至关重要。本研究针对67款商用钠离子电池，在不同温度、C倍率（C-rates）以及放电深度（Depth of Discharge）条件下开展了系统性老化分析。研究分析了电池初始的单体间一致性偏差，以及与容量衰减、内阻上升相关的老化轨迹（Aging Trajectories）。结果表明，循环倍率对老化轨迹无显著影响，而较小的放电深度可显著减缓电池降解。25℃与40℃条件下的降解梯度较为相似；而在-10℃环境中，电池出现了快速容量衰减现象，该现象可归因于不可逆钠析镀（Sodium Plating）。此外，本研究明确了四类不同老化类别的降解模式。由于部分老化测试因低电流倍率与荷电状态（State of Charge, SOC）下气体触发电流中断装置（Current Interrupt Device, CID）而终止，本研究针对特定条件下的产气现象提出了两种假说，认为正极-电解液副反应中气体消耗不足，或是固体电解质界面（Solid Electrolyte Interphase, SEI）失稳，均可能为产气的潜在诱因。综上，本研究针对商用钠离子电池的老化行为开展了极具价值的深度分析，探讨了温度、C倍率与放电深度对老化行为的影响，并公开相关数据以供后续研究使用。