After about 20 minutes of flying the current into the battery went from 20 to 30 to 40 to 50 amps before the alternator circuit breaker (CB) blew. I shut off the master and let everything cool off for 15 minutes. I am sure glad that I have magnetos. I hand flew the plane using my handheld Garmin. I then reset the CB, turned on the master and then the alternator. The system charged for about 3 minutes and then shutdown again. I turned the charging system back on every 10 minutes for the next 2 hours and finally the charging current went below 40 amps and stayed on. I tested the battery temperature by hand and estimate that the battery got to about 140°F.