This is not about money.
Its about him feeling that you are working together towards a shared goal. He mentioned savings but it could have been about a second home or better pensions or a kitchen extension.
The fact is that right now he is working and earning to facilitate you living the dream. You are happy and fulfilled and the fact that he has brought this up, suggests that he isnt.
So I would start the conversation by asking whether he is happy, and if he isnt (he isnt), why. Is it really about savings or is he unhappy in his job but feels pressure to stay in it to sustain his wife and family's lifestyle, for example.
Then you dont say that you dont want to do paid work, because that is frankly selfish. You are already working, so why the hell not monetise the work in a different area to home and volunteering? Make a new plan. Perhaps he stops chasing the big job (there is always a bigger job to aim for) and you earn too. Just that lifting that pressure on him could make a huge difference to your marriage. It may not make that much of a difference in practical terms on his working life, but the knowledge that he isnt carrying the whole financial burden himself will change so much. Its not "me" anymore, its "us". You may well find that it creates a new emotional intimacy between you as there is a more equal level of mutual respect. Sounds like there isnt much respect on either side, more expectation on yours and resentment on his.
When one partner is happy and ignores the fact that the other isnt, the end is inevitable. Do you want your marriage to end? Because "No I wont go back to work, I am happy as I am" is as destructive as what my ex said to me before we divorced "I dont know why you are unhappy, because I am fine so its your problem to solve." So I did, with a Decree Absolute. He may well solve this his way, possibly (no means defintiely, but it is a risk) including with a woman who is happy to work and pay her own way.......
Not saying any of this to have a go, but because this is the reality of life. Why do you think you read so often on MN of SAHM's being left for a younger woman with a good career?