The Pi-Top  DIY Edition is a well-designed Raspberry Pi 4 Case with a built-in battery, power management system and MCU cooling system.
It doesn't stop there. The case includes a 128x64 OLED screen, a built-in 1W loudspeaker and full access to all Raspberry Pi interfaces such as Ethernet, USB, Dual-HDMI and GPIO ports.
Simply add a Raspberry Pi 4 and you are ready to go. The power supply benefits from USB-C Power Delivery which means you won't run out of power.