If you use that address, any judgements, law-suits, insurance claims, prosecutions, product liability claims, Revenue sheriff collection orders may be registered against your partner's home. This may impinge upon his/her credit rating, ability to sell the property or raise a top-up mortgage.
Its not a good idea, even if your partner agrees. These and other wide-ranging and related issues have all been discussed here before.
BTW, you would not be working from home - you would be running a business at someone else's home.