My battery light will come on and display says emmission ok then the next day emmission will come on and display charging system ok.

Disconnecting the battery only stops the warnings temporarily - it does not resolve anything. Troubleshooting hands on with proper test equipment is needed to see what is going on with the multiple systems affected here. The battery light coming on indicates a lack of proper charging system operation. The emissions control warning indicates a problem with one of many emissions related components. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops