It is highly recommended to inspect and clean your drone's battery cable connections at the end of each cleaning day. Bleach and other chemicals can cause a buildup/corrosion which can lead to an overheating of the connections. In some cases, this can cause the battery cable to seize to the electrical connector on the drone. Proper maintenance will prevent this.
Please follow this video: How to Clean Your Battery Connections
You may need to use an exacto-style knife to scrape out any hardened or stuck contaminants.