2, the reasons are as follows:
(1) with the battery will generally involve safety issues, safety issues are the most countries in the certification. For example, IEC/EN62133 and other tests, CCC certification, North American NRTL certification, UL certification and so on. Another is the safety of transportation, generally have UN38.3 and other certifications.
(2) Since there is a battery, it will involve energy efficiency issues, energy efficiency, such as the U.S. CEC and DOE certification, the European ERP issues.
(3)Toxic substance issues, such as ROHS, REACH certification in EU.
The above is for reference only, hope it is useful to you.