IEEE 1115-2025

This recommended practice covers the sizing of nickel-cadmium batteries used for standby operation in stationary applications. Recommendations are provided for applications including, generating stations, substations, telecommunications, switchgear and control systems, compressor stations, emergency lighting, uninterruptible power supplies and engine-starting applications. The following topics are beyond the scope of this document: • Installation, maintenance, qualification, and testing procedures which are covered in IEEE Std 1106; • Consideration of battery types other than nickel-cadmium; • Renewable energy systems (e.g., wind turbines and photovoltaic systems) that may provide only partial or intermittent charging which is covered in IEEE Std 1144; • Design of the dc system and sizing of the battery charger(s) which is covered in IEEE Std 946.

The purpose of this recommended practice is to provide proven and standardized sizing techniques for nickel-cadmium batteries. The sizing methods in this document take normal usage factors into account and form the basis for reliable battery operation.

Revision Standard - Active. The sizing of nickel-cadmium batteries used in standby operation for stationary applications is discussed in this recommended practice.