The volume of end-of-life automotive batteries is increasing rapidly as a result of growing electric vehicle adoption. Most automotive lithium-ion batteries (LIBs) are recycled but could be repurposed as second-life batteries (SLBs) since they have 70–80% residual capacity, which can be adequate for stationary applications. SLBs have been proposed as potential, inexpensive, low-carbon energy storage for residential and utility-level applications, with or without photovoltaics (PV). However, it is unknown whether SLBs will be better than new batteries and whether SLBs will provide similar cost and carbon emission reduction for the different stationary applications in all locations. This work compared the levelized cost of electricity and life-cycle carbon emissions associated with using SLBs and new LIBs in the US for three energy storage applications: (1) residential energy storage with rooftop PV, (2) utility-level PV firming, and (3) utility-level peak-shaving, leading to a total of 41 scenarios. SLBs reduced the levelized cost of electricity by 12–57% and carbon emissions by 7–31% compared to new LIBs in the considered applications, with higher reductions for utility-level applications. SLBs still provided benefits at the residential level when compared to rooftop PV alone by reducing the levelized cost by 15–25% and carbon emissions by 22–51%, making SLBs attractive to residential consumers as well. SLBs offer an opportunity to utilize an end-of-life product for energy storage applications, provided the uncertainty in SLB quality and availability is addressed.

随着越来越多的电动汽车采用，报废汽车电池的数量正在迅速增加。大多数汽车锂离子电池（LIB）可以回收，但由于它们的剩余容量为70-80％，可以满足固定应用的需要，因此可以重新用作第二次使用的电池（SLB）。已经提出了SLB作为具有或不具有光伏（PV）的住宅和公用事业级应用的潜在，廉价，低碳的能量存储。但是，尚不清楚SLB是否会比新电池更好，SLB是否会为所有位置的固定应用提供类似的成本和碳排放减少量。这项工作比较了美国在三种储能应用中使用SLB和新LIB所产生的平均电力成本和生命周期碳排放成本：（1）带屋顶光伏的住宅储能，（2）公用事业级别的PV固定，以及（3）公用事业级别的调峰，导致总共41种情况。与考虑中的应用中的新LIB相比，SLB降低了平均水平的电力成本，降低了12％至57％的碳排放，降低了7％至31％的碳排放，其中公用事业级应用的降低幅度更大。与仅使用屋顶光伏发电相比，小型SLB仍在住宅层面提供了好处，可将平准化成本降低15–25％，碳排放降低22–51％，这也使SLB吸引了住宅消费者。SLB提供了将寿命终止的产品用于储能应用的机会，