LiBH₄ has been considered as one of the most promising energy storage materials with its ultrahigh hydrogen capacity, which can supply hydrogen through hydrolysis process or realize hydrogen-to-electricity conversion via anodic oxidation reaction of direct borohydride fuel cells (DBFCs). However, the realization of practical hydrogen applications heavily depends on the effective synthesis of high-purity LiBH₄ and recycling of the spent fuels (LiBO₂·xH₂O). The present work demonstrates a convenient and high-efficiency solvent-free strategy for regenerating LiBH₄ with a maximum yield close to 80%, by retrieving its by-products with MgH₂ as a reducing agent under ambient conditions. Besides, the hydrogen released from the regeneration course can completely compensate the demand for consumed MgH₂. The isotopic tracer method reveals that the hydrogen stored in LiBH₄ comes from both MgH₂ and coordinated water bound to LiBO₂. Here, the expensive MgH₂ can be substituted with the readily available and cost-effective MgH₂−Mg mixtures to simplify the regeneration route. Notably, LiBH₄ catalyzed by CoCl₂ can stably supply hydrogen to proton exchange membrane fuel cell (PEMFC), thus powering a portable prototype vehicle. By combining hydrogen storage, production and utilization in a closed cycle, this work offers new insights into deploying boron-based hydrides for energy applications.

LiBH ₄以其超高的氢容量被认为是最有前途的储能材料之一，可以通过水解过程提供氢气或通过直接硼氢化物燃料电池（DBFC）的阳极氧化反应实现氢电转换。然而，氢的实际应用的实现很大程度上取决于高纯LiBH ₄的有效合成和乏燃料（LiBO ₂ ·xH ₂ O）的回收。目前的工作展示了一种方便高效的无溶剂再生策略，_{通过用 MgH 2回收}其副产物，最大产率接近 80%在环境条件下作为还原剂。_{此外，再生过程释放的氢气可以完全补偿消耗的MgH 2}的需求。_{同位素示踪方法表明，LiBH 4}中储存的氢来自MgH _{2和与LiBO 2}结合的配位水。这里，昂贵的MgH ₂可以用容易获得且具有成本效益的MgH ₂ -Mg混合物代替，以简化再生路线。值得注意的是， CoCl ₂催化的LiBH ₄可以稳定地向质子交换膜燃料电池（PEMFC）供应氢气，从而为便携式原型车提供动力。通过将氢的储存、生产和利用结合在一个封闭的循环中，这项工作为在能源应用中部署硼基氢化物提供了新的见解。