Yes, that's what I said. It's how every diagram from Victron shows it being done. It's how many people on this forum show how it's done.
One thing you haven't done is explain how you believe it should be done. It's doesn't help to state we are wrong but with no explanation of why it's wrong and how it should be done. Please show us the correct way.
First I'll address your requests for me to "explain how it's done".
I'm not saying you're doing anything "wrong" first of all. I'm only arguing against the term "ground" in the context here and that I disagree with the entire industry doing so as well.
Regarding your method however, since you keep insisting:
The manuals that suggest "grounding" don't show anything like what you're suggesting for this random epever model I just downloaded. I don't know what OP is using to get more specific.
It simply shows a negative wire to a not pictured (but we can just imagine) bus which is then itself "grounded". It then mentions "grounding" the case without any information on how or what size wire to use, just that it should be attached somehow.
Here's a screenshot from a victron system example off their website. It also shows no such oversized redundant ground wires installed alongside and equal in size to the negative from these devices.
My two victron devices that I own both make no mention of doing so either. In fact there isn't even any provision on either one of them to ground the case as the mounting flanges are anodized and thus poor connectivity would be had, and the only screws anywhere on it are miniscule or in locations that would be difficult to get even a small ring terminal on.
I'm fact there is no mention of "grounding" any of it in my DC-DC charger manual.
But that's not what I care about lol. Overkill your "grounds" all it want.
It's this usage of the term "ground" I am protesting, not necessarily the wiring. Not sure why you keep asking that.
I didn't say anything should necessarily be done differently. I simply stated your suggestion to double up on the huge negative wire is overkill.
Do it if you want. It's electrically identical to simply not running anything extra at all and just putting a small wire from the case to the chassis. Overkill is fine if you have money to burn on wiring.
I'm only suggesting it should not be called a ground unless it's either earthed or specifically used at a different potential to allow ground fault protection to work, which would be the case for an AC install so long as the neutral isn't bonded to the chassis, which would be rather unsafe.