Chuck(G)
25k Member
Depends on the setup. If the battery connects through the external 4-pin header, it's not charged by the motherboard. So take one of these widgets and hook one side across the battery and the other to +5. If you're dealing with the on-board charging circuit, measure the applied voltage without a battery present. If it's under 4.2V, you're good as-is. Otherwise use a blocking diode and a widget powered off the +5 motherboard rail.