Yes, it needs to be cleaned up ASAP!
Get as much water on it as you can, start with an open hose, low pressure to flush without splattering it on yourself and what might not already be contaminated.
Then switch to high pressure wash, like a pressure washer if you have one.
Remember any dirt that may have soaked up the acid will hold it and cause corrosion of anything it is in contact with. The cleaner you can get it, the better.
Follow that with an alkaline type liquid detergent or baking soda and water. A pump up sprayer will help get it into difficult areas.
Wonder why the battery exploded? Something short it out? Overcharging?