The desire for practical utilization of rechargeable lithium batteries with high energy density has motivated attempts to develop new electrode materials and battery systems. Here, without additional binders we present a simple vacuum filtration method to synthesize nitrogen and sulfur codoped graphene (N,S-G) blocking layer, which is ultra-lightweight, conductive, and free standing. When the N,S-G membrane was inserted between the catholyte and separator, the lithium–selenium (Li–Se) batteries exhibited a high reversible discharge capacity of 330.7 mAh g⁻¹ at 1 C (1 C = 675 mA g⁻¹) after 500 cycles and high rate performance (over 310 mAh g⁻¹ at 4 C) even at an active material loading as high as ~ 5 mg cm⁻². This excellent performance can be ascribed to homogenous dispersion of the liquid active material in the electrode, good Li⁺-ion conductivity, fast electronic transport in the conductive graphene framework, and strong chemical confinement of polyselenides by nitrogen and sulfur atoms. More importantly, it is a promising strategy for enhancing the energy density of Li–Se batteries by using the catholyte with a lightweight heteroatom doping carbon matrix.

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对具有高能量密度的可再充电锂电池的实际利用的期望激发了开发新的电极材料和电池系统的尝试。在这里，在没有其他粘合剂的情况下，我们提出了一种简单的真空过滤方法来合成氮和硫共掺杂的石墨烯（N，SG）阻挡层，该层超轻，导电且自立。当插入该阴极电解液和分离器之间的N，SG膜，锂-硒（锂Se）的电池表现出330.7毫安g的高可逆放电容量^-1 1个C（1 C =675毫安克^-1）之后500次循环和高倍率性能（4 C时超过310 mAh g ^-1），即使活性物质负载高达〜5 mg cm ^-2。这种优异的性能归因于电极中液体活性材料的均匀分散，良好的Li ⁺离子导电性，在导电石墨烯骨架中的快速电子传输以及氮和硫原子对聚硒化物的强化学限制。更重要的是，通过将阴极电解液与轻质杂原子掺杂碳基质一起使用，这是提高锂硒电池能量密度的一种有前途的策略。

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