I just replaced the battery in my S8+. When I plugged it in to be conditioned, the red light began blinking. I left it on the charged for a couple of hours with no change. I assume I reassembled it wrong, but I do not see anything out of place.
Did you replace the battery using an aftermarket battery or OEM? Either way it shouldn't matter much in terms of turning on. You should check using the multimeter if the battery is in a healthy voltage range for that specific battery. the cell might be faulty. You could also have potentially broken the connector of the battery or have not plugged it in properly. Hope this helps
