MacBook without battery kernel_task 100% CPU utilization

The procedure mentioned here, involving the removal of one specific system file, will probably disable the sensor check and prevent the kernel task from gobbling up your CPU, while waiting for your battery: https://apple.stackexchange.com/a/146381/226332

MacBooks - all types and models - are capable of demanding - and getting - 20% to 45% more power from the battery than is available on the charge supply. The machine runs from the batteries exclusively at all times, unless the battery is removed or a problem is detected and it is switched out of circuit, whereupon the machine will self-throttle so as to not exceed the available charge current.