For what I know, a BMS controls the current going into the battery. If the charge source (this case your alternator) was only capable of producing 3 amps (absurd, I know) the BMS likely wouldn't control the current. It will merely limit the battery charged voltage or the battery discharged voltage. If the battery reaches full charge it stops charging. If the battery is being drained it disconnects the battery.

While I don't know the exact charging profile it will give a max allowable current into the battery based on its chemistry. Now that alternator: If it produces 130 amps the battery isn't going to take that much current. The BMS will limit to the proper charge profile. As the state of charge (SOC) climbs from discharged toward charged at some point it's going to further reduce the amount of current feeding the battery. The voltage just needs to be a few volts higher than the battery max charge voltage. That's why they call it a Battery MANAGEMENT System. It controls all that. If you purposely limit the current then the BMS can not add current to the charge profile.

 

Never heard that.
If the alternator is running below its maximum current rating, there should be no significant effect on its life.

Who are these "some"?

The "some" are thousands of people that might have no idea what they are talking about.

Seems to fall into the category of does it make a difference running at engine at wide open throttle or at some lesser throttle setting with respect to engine longevity?

Now I would agree that alternators and engines are not the same. And feel that with alternators it is about cooling. Given sufficient cooling an alternator should be able to output full electrical power without affecting its service life.

One company intentionally runs at alternator at low speed while having it produce maximum power. Smoke soon ensues. Trying to sell a gizmo they proclaim the alternator from being damaged.

 

OK, in post#19 I neglected to explain that the "solid batteryconnection" was TO THE FIELD, not to the output. That scheme has worked to power assorted power tools with 120 volt UNIVERSAL MOTORS , and those motors ran very well on the DC supply.
In addition, I was ONLY talking about alternators on the engines of motor vehicles, not those used with separate drive sources just for battery charging. THAT application is a separate topic completely.
Of course, battery charging in itself includes different modes, FAST CHARGING being quite different from the other modes, such as routine and standby charging.

 

Given sufficient cooling an alternator should be able to output full electrical power without affecting its service life.

So what is the current/power rating of your alternator, and what is driving it?