Investment Rating - The report rates the electrical equipment industry as "Positive" [3] Core Insights - The calendar life of batteries is a critical indicator determining the actual lifespan of energy storage batteries. The key to improving calendar life lies in mitigating battery degradation, which is influenced by four main factors: LAM (loss of active material), LLI (lithium loss), LE (electrolyte), and RI (resistance) [2][12][14] - The report anticipates a turning point in the improvement of domestic energy storage battery calendar life, projecting it to gradually reach the 15-year mark. Tesla's Megapack has a warranty period of 20 years, and high calendar life energy storage battery products in China are expected to begin mass production in 2025 [2][67] - Investment opportunities are suggested in sectors related to lithium replenishment agents, liquid cooling systems, battery management systems (BMS), and energy storage batteries [2] Summary by Sections Battery Calendar Life and Degradation Mechanism - The calendar life of batteries is defined as the time a battery can maintain certain performance indicators while in a long-term storage state. It is influenced by various factors, including temperature and state of charge (SOC) [12][13][24] - Battery degradation is primarily caused by LAM and LLI, with power degradation linked to LE and RI. The degradation characteristics are non-linear and can be divided into three stages [14][24] Key Points for Improving Calendar Life - The report identifies three main areas for improving calendar life: lithium replenishment materials, liquid cooling systems, and BMS [27] - Lithium replenishment is emphasized as a key focus for addressing LLI, with potential improvements in cycle life by 50%-200% through the use of lithium replenishment agents [32][34] - Liquid cooling systems are highlighted for their ability to manage temperature more effectively than air cooling, which can significantly extend battery life [50][60] Domestic Energy Storage Battery Outlook - The report suggests that domestic energy storage battery calendar life is on the verge of significant improvement, with expectations for products to achieve a calendar life of 15 years by 2025 [67] - Tesla's Megapack serves as a benchmark with a 20-year warranty, while domestic products typically offer warranties of only 5-10 years [67] - The report notes that domestic companies are also developing long-life battery solutions, with NIO and CATL planning to launch products with a lifespan of 15 years [73]