I work full time and have hit a point in my career where I wish I had more business skills. I am the main income for my family, so online is my best option.

I know there are many online MBA programs, but through my research I have found online business certificates. For example - http://kelley.iupui.edu/undergrad/academics/foundations-certificate/.

Has anyone completed an online business certificate? Did it help you build the business skills you needed? How did employees perceive the certificate? Any advice/thoughts would be great to help me make this decision.

I don't think these unusual undergraduate qualifications are well understood. For much less than the cost of this Kelley certificate, you could take an AA degree from a regionally accredited school, or the LSE's diploma for graduates. Either way, these are academic programmes rather than focussed on developing professional competencies.

PS The suggestion about Coursera or edX below is very useful.

What exactly are you looking for? These certificates aren't in any way a substitute for an MBA, which would provide things like networking opportunities and career services support.

I guess if you were just looking for something to put on your resume, something like this would work. If it were me though, and all I was looking for was a foundational level of business knowledge, I would find these course equivalencies in online outlets like Coursera or edX.