I just became aware of new rechargeable portable shower, that also heats the water.
Check it out: https://www.amazon.com/WADEO-Portable-Fahrenheit-Rechargeable-Switching/dp/B0DJVSX59V?dib=eyJ2IjoiMSJ9.R0T13cAePHaYv25U7u4EdcL9mXTzCsoGtDzKSk4RH9_fZ_uLbrirvx3bUNw6b9yaMvzF7gaj5xmNrh97aeCq0xYM1E0NhdpB-FhFLz6UUYyogia4iYnVt9vkKdgj4UwrANM7IBpVAgCfLfyVOmZzxAo2NElu9s8kzqiZATcrKeRLZE1zTkUk4KjcGyLkEML-JY5QSU8-CFLyxbo7xgCC13dMck2a_mxUj5ED7P5Fi5KEh_F1TePgCYmFHbBxjHC01iYcbOLZUZbBoMdz0H9WnJwcOI5uEbFtPqzDRKUVAWg.Q3syWWBWrn-Y1uZQA4jQcCKz2gdRM-Fg1wyBW_iJIp4&dib_tag=se&keywords=60%2Bsecond%2Bshower&qid=1771616820&sr=8-47&th=1