I control the charging of my lithium battery with a multiplus 800VA . The Multiplus is also using to charge the starterbatterie with the 4A Port. I noticed that I have a permanent power on the 4A line when the charger no longer has any power. From this I conclude that the starter battery is charged with the lithium battery in the situtuation without external charge power. Unfortunately, this is a problem for me because the BMS can't intterupt this.