Based on this product's specifications, here are some alternatives and similar models
Karcher Battery Power 18/50 Lithium-Ion Battery 18V 5.0Ah
Summary description:
The Karcher Battery Power 18/50 is a high-performance 18V lithium-ion battery with a 5.0Ah capacity. Designed for use with Karcher 18V cordless power tools and cleaning equipment, it features Real Time Technology with an integrated LCD display to show remaining runtime, charging time, and state of charge. This durable battery ensures consistent power output and reliable performance for various household and garden maintenance tasks.