E-Glide no longer starts after voltage drop….

Hello Harleygemeinde, am new here in the forum and hope to get help from the “Profis”. Drive for 3 years an E-Glide Ultra Classic 95`injection. Had after some time the problem, that when starting was only a slap. First the battery was replaced (but only cheap battery), which helped after some time also nothing. According to a “Harley screwdriver ” the magnetic switch was defective. So exchange with original Harley battery. Now I have the same problem again. If the battery is 100% charged, the E-Glide starts immediately. During the drive the voltmeter shows 13 volts. Instead of me the HD and then try to start again, I have again only the “cracking”. After recharging (but must reach again at least 12 volts) works again. Hanging too many consumers on it can be pulled erndwo side current…. maybe you have me a solution. Merci Andy Andy