在大力发展新能源背景下，储能日益成为重要的战略手段。含水层压缩空气储能（compressed airenergy storage in aquifers，简称CAESA）作为一种新型储能技术，因具有分布广、规模大等优势正受到关注，在勘探开发程度较高的油区含水层开展压缩空气储能具有更显著的优势。CAESA中，盖层系统的密封性控制着储库容量和安全性。充分挖掘盖层系统的封闭潜力需要依靠定量评价指标。针对该类工程特征，提出了一种最大封闭压力模型（Pmax）作为盖层（单元）封闭能力的定义，并通过数学建模给出了具体的确定方法。该模型可包容各类封闭机制，同时首次从数学物理上解释了盖层厚度的封闭机制。该指标可以作为选址阶段度量盖层封闭性的单一主控指标使用。以该指标为基础，结合系统的短板原理，定义了适用于整个盖层系统封闭性度量的盖层安全封闭压力指标Psafe，并给出了计算方法流程，可以在工程开发设计阶段采用。以中国石化胜利油田规划建设的KD642-7示范工程应用为例初步印证了该模型的合理性。In the context of the rapid development of new energy technologies

energy storage has emerged as a crucial strategic capability. As a new energystorage technology

compressed air energy storage in aquifers (CAESA) isreceiving attention due to its advantages of wide distribution and large scale.It has more significant advantages in carrying out compressed air energystorage in aquifers with high exploration and development levels in oil regions.In CAESA

the sealing performance of the caprock system controls the storagecapacity and safety. Fully tapping into the sealing potential of the caprocksystem requires the use of quantitative evaluation indicators. This article proposes a maximum sealing pressure model (Pmax model) to define thesealing capacity of a caprock segment

and provides a methodfor determining Pmax viamathematical modeling. This model can accommodate various sealingmechanisms

and for the first time

it explains the sealing mechanism of thethickness of the caprock layer from a mathematical and physical perspective.This indicator can be used as a single indicator to measure the sealingperformance of the caprock layer during the site selection stage. Based on thisindicator and in combination with the short-board principle

we propose thesafe sealing pressure index Psafe to quantify the sealing performance of the entire caprock system. We alsoprovide the calculation method and a flowchart

which can be applied during theengineering development and design stage. Finally

using the KD642-7pilot project planned by Sinopec Shengli Oilfield as an example

the model’svalidity has been preliminarily demonstrated.