Contents:

The battery is in the trunk under the compartment cover.
When replacing the battery, disconnect the negative (-) cable (1) and remove the positive (+) battery fuse box (2).
Remove the battery mounting bracket (3).
WARNING - Touching metal surfaces in the trunk under the compartment cover

Do not touch metal surfaces in the trunk under the compartment cover while the engine is operating or hot. Doing so could result in serious personal injury. Turn the engine off and wait until it cools down or wear gloves to replace the battery from the luggage room.
Your vehicle has a maintenance-free, calcium-based battery.
When recharging the battery, observe the following precautions:
Reset items
Items should be reset after the battery has been discharged or the battery has been disconnected.
Kia Stinger (CK) 2018-2023 Owner's Manual: Rear Bumper
Components and components location Components 1. Rear bumper cover assembly 2. Rear bumper side under cover 3. Rear bumper side lower bracket 4. Rear bumper side bracketKia Stinger (CK) 2018-2023 Owner's Manual: 4 Wheel Drive (AWD) System
Special service tools Special Service Tools Tool Name / Number Illustration Description Oil seal installer (Main Shaft) 0K473-J5100 Installation of transfer case oil seal (Main Shaft). Used with the handle (09231-H1100) Oil seal installer (Rear Flange) 0K473-J5200 Installation of transfer case oil seal (Rear Flange).