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: Cowl Cross Bar Assembly
Components and components location Component Location 1. Cowl cross bar assembly Repair procedures Replacement Put on gloves to protect your hands. • Use a plastic panel removal tool to remove interior trim pieces without marring the surface.Kia Stinger (CK) 2018-2023 Owner's Manual: ISG (Idle Stop and Go) system
Your vehicle may be equipped with the ISG system, which reduces fuel consumption by automatically shutting down the engine, when the vehicle is at a standstill. (For example : red light, stop sign and traffic jam) The engine starts automatically as soon as the starting conditions are met. The ISG system is ON whenever the engine is running. ✽ NOTICE When the engine automatically starts by the ISG system, some warning lights (ABS, ESC, ESC OFF, EPS or Parking brake warning light) may turn on for a few seconds.