Air carrier Captain reported during preflight a gate agent asked the Captain for handling guidance of a Lithium battery powered scooter. After resolving the handling issue the Captain suggested better training of ground personnel and also improvement of the flight crew FOM.

Narrative

After coming back in the jetway after doing the walk around; the passengers were pre-boarding. There was a gate agent and a passenger with what I would have described as an electronic scooter getting ready to board. They advised me that the device had lithium-ion batteries and asked me what to do with it. I told them that I would contact a ramp agent and follow up with my manuals. I told my student to continue to prep the A/C (aircraft) for departure and that I would handle this issue. I started searching the FOM for guidance when the ramp lead came to the flight deck. He told me that their policy was to remove the batteries(they were easily removable) and then stow both the device and the batteries in cargo bin. I asked if they secured the batteries in anything; and he said no. This didn't sound correct to me; so I continued to search the FOM. The first thing that I found in the FOM was under a Load Closeout notification. I had this bookmarked; for when I teach my students about the load closeout. It says 'NOTE: Dry ice and wheelchair batteries loaded as passenger-checked baggage are shown as XX and XY on the load closeout and do not require a NOTOC.' Notice that this does not say what kind of batteries. I did not believe that lithium-ion batteries qualified for that; so I continued to search. I searched wheelchair batteries and that returned the same result of what I'd just read. I then searched lithium-ion batteries; and read through the long list of restricted articles; and came to a page ; with several lines of information on lithium-ion batteries. At the bottom was the entry for Lithium-Ion(Wheelchairs/Mobility Aids/Stroller) in Device or as a spare; which is hyperlinked to lithium-ion batteries. This listed 'When Battery Is Easily Removable.' This section seemed like the logical choice; but I found the whole thing confusing. I decided to call the dangerous good hotline for advice. They told me that I need to talk to someone else; and gave me the number. I called them and they told me that my choice was the correct one. I also contacted ZZZ Chief Pilot since he was once a duty pilot and I have his number in my phone. He helped me with my search. I called back the ramp agent and he told me that they never handle those devices like that; that they always put both the device and the batteries in the bin. He stated that as a matter of fact; that was the only way for him to scan the device as it went in the bin. I told him to scan it that way; but we were storing the batteries in a bag by the customers seat as advised. On the close out; we received the XY notification; but we departed anyway since we knew where the batteries were. Cause: Task saturation with a late arriving aircraft and doing OE (Operating Experience) with a new CA (Captain); that was also struggling to find the answers. FOM design.Suggestion: Better; more consistent training for gate agents. Improvements in the FOM to make information easier to find. The phase of flight construction of the FOM does not help that. Too many subject are scattered over too many areas. If you don't know the exact word to search; for example wheelchair vs. mobility device; you may miss information. In hindsight; I should have started with the duty pilot.