Potassium ion batteries (KIBs) are emerging notably due to the reversible K⁺ intercalation into graphite. So far, optimization of graphite electrode formulation remains, however, to be investigated. This work thus proposes to optimize ionic (porosity) and electronic percolation networks as well as mechanical properties of graphite electrodes for KIBs. To do so, carbon black amount (CB) and electrode calendering is first adjusted. Then carboxylated styrene butadiene rubber (SBR) is used, with different amount and functional groups contents, as co-binder with carboxymethyl cellulose (CMCNa). The best electrodes, made of 95/5/8/2 wt.% of graphite(SLP30)/CB(C65)/CMCNa/SBR(Synthomer) with 2.4 mg cm⁻² loading and 35% porosity, deliver ∼250 mAh g⁻¹ during depotassiation at 5C with only ∼0.3 V polarization and 205 mAh g⁻¹ during potassiation at 1C (3-electrodes configuration). In addition, no capacity loss is observed after 55 cycles at C/5 potassiation/1C depotassiation due to a low electrode volume expansion (11%) compared to 24% without SBR after only 35 cycles. These results highlight that appropriate SBR significantly improves the electrode structure/cohesion/elasticity (i.e. volume expansion management), leading to better power performance and capacity retention of graphite electrodes for KIBs. Finally, considering that further improvements are expected by tuning electrolyte formulation, this work will benefit to the development of high energy KIBs.

钾离子电池 (KIB) 的出现主要是由于可逆的 K ⁺嵌入石墨。然而，到目前为止，石墨电极配方的优化仍有待研究。因此，这项工作提出优化离子（孔隙率）和电子渗透网络以及用于 KIB 的石墨电极的机械性能。为此，首先调整炭黑量 (CB) 和电极压延。然后使用不同数量和官能团含量的羧基丁苯橡胶（SBR）作为与羧甲基纤维素（CMC Na）的助粘合剂。最好的电极，由 95/5/8/2 wt.% 的石墨 (SLP30)/CB(C65)/CMC Na/SBR(Synthomer) 制成，负载量为 2.4 mg cm ^-2和 35% 孔隙率，可提供 ∼250 mAh g ^-1在 5C 的去钾过程中，在 1C 的钾化过程中只有 ∼0.3 V 极化和 205 mAh g ^-1（3 电极配置）。此外，由于电极体积膨胀低（11%），在 C/5 钾化/1C 去钾下 55 次循环后没有观察到容量损失，而仅 35 次循环后没有 SBR 的容量损失为 24%。这些结果突出表明，适当的 SBR 显着改善了电极结构/内聚力/弹性（即体积膨胀管理），从而提高了 KIB 石墨电极的功率性能和容量保持率。最后，考虑到通过调整电解质配方有望进一步改进，这项工作将有利于高能 KIB 的开发。