Yuck, yuck, yuck. I'm glad that you are going to go to counseling, and hopefully he will join you. I really don't get the bedpan/urine jar thing--I mean, I can see that type of thing in an emergency or certain situations (like, say, many people have a pee bottle when camping during cold weather so they don't have to get out of the tent and freeze in the middle of the night.) But for that to be happening inside a home without a medical reason sounds like there is some disordered thinking/behavior going on there.
Frankly, my first thought was, "is he a heavy pot smoker?" You don't have to answer that on here if you don't want to, but those types of behavior and thinking are often associated with heavy recreational drug usage IME. And concern for hygiene is one of the things that can really go out the window with drug use. Has he always been this messy/dirty and done these behaviors? Are these attitudes new? Or is it just more problematic for you right now because you're working more and have a toddler and are having more trouble keeping up with the cleaning? It sounds like he's acting like a big child--and not a well-behaved one either, but a disturbed, narcissistic, and acting-out child!!! Seriously, my almost-three year old doesn't even pull that kind of stuff--if she spills something I calmly tell her to go get a rag and clean it up, and she almost always does without a problem. Often she'll put her dirty clothes in the hamper on her own initiative without prompting or go put her garbage in the trash can. These are very basic principles that a two year old can master, so when an adult can or does not seem to understand that you can't just leave food spills or bodily fluids wherever, there is something not quite right there somewhere. Did he behave this way with his mother growing up, or with the household help?
This sounds drastic but I might consider documenting this with dated photos (and keeping them in a safe spot, maybe with a friend.) Because it sounds to me like he is sort of downplaying your side of things and also implying that he is the better parent, and that you're abusive, and all of this doesn't add up to a nice scenario. If he turns around and there is a happy ending to this then you will have some great "before" pics to put with your "after" pics of a clean and sanitary house. If not, then you will have some documentation to back up your claims that he is not maintaining a reasonably sanitary home environment suitable for children. I'm sorry to be going down that road, but this just doesn't sound like a good situation.
Is there a third party who you could get to talk to him? (As in, a physician, a fireperson, clergyperson, somebody who's had their house suddenly inspected by CPS? Something like that?) Seriously, I don't know how bad it is but there are health and safety issues here. It's one thing to have an Oscar/Felix Odd-Couple type of marriage, it's pretty common to have a clutter-bug and a neatnik married to each other, but I think you really need to at least focus on the issues where you're getting into actual filth/squalor--for me that would be a few basic categories: Excrement in any form (as in pee bottles, bedpan, poopy diapers), food waste including containers and wrappers being left around, hazardous stuff (like leaving medications or other toxins within reach of the kids) and trash. This is totally unacceptable, and I would have to really seriously put my foot down about those things, and focus your efforts on those things. Leaving his socks on the floor or having a messy desk or leaving an empty coffee cup in the car might be untidy and annoying if you're more on the clean freak side, but it isn't the end of the world, but this is a whole other level of dirty/messy. I mean, seriously, how is your 20 month old going to learn to potty train if his father is peeing/crapping all over the place??!!!