This experimental dataset comprises experiments conducted on a highly instrumented heat pump test bench for Carnot battery applications. The heat pump employs a laboratory-scale reciprocating compressor and is coupled to a two-tank sensible thermal energy storage. The reported data include temperatures and pressures between all main components, as well as flow rates of all fluids and electrical power consumption. This enables a detailed analysis of individual heat pump components and supports model fitting and validation, for example for a compressor model, which is also included. The dataset provides raw sensor signals as time series, time-averaged values, and calculated performance metrics (e.g., COP, compressor efficiencies, and exergy losses). Descriptive metadata are included to facilitate understanding of the experimental setup and the applied boundary conditions. A total of 17 experiments are included, covering different stationary operating conditions with varying storage temperatures, compressor frequencies and working fluids (propane, butane, and a zeotropic propane/pentane mixture). The dataset is published as a preprint at https://doi.org/10.36227/techrxiv.176478421.10869135/v1 (accepted at 15th IEA Heat Pump Conference), where the data are described and analysed in detail. All data presented in the publication are included in this repository. The dataset is explained in detail in the file README_overview.md. Please read this first.