vic008
Active member
Is a dc-dc unit needed if running a Balmar mc 614 with a lithium battery? Thank you
The issue with direct charging of lithium with an alternator is what happens if your lithium battery bms detects a fault and shuts down the battery. This then leaves the alternator with nowhere to dump its charge. The alternator diodes will pop and you then have no alternator output. Considering that the bms will have several fault modes where it can shut down charging, this fault scenario is a real risk. You can add an alternator protector for about £80 but I think these are one time protection devices and not a fit and forget. The quality of the lithium battery and how much information you have available via Bluetooth could reduce the risk of a bms disconnect. Setting the alternator charge voltage well below the bms cut off charge voltage would help.Is a dc-dc unit needed if running a Balmar mc 614 with a lithium battery? Thank you
I thought you just ran the lithium bank at a slightly lower voltage than optimum, and that this was the way hybrid lithium worked? The lead-acid batteries get 100% charged, the lithium ones never do but they last longer because of it?It is if you also have a Lead Acid starter battery, windlass battery or bow thruster battery.
The smarts help with a charge profile but you shouldn't join lithium with lead as one of them will be at the wrong voltage.
I don't think that works. Optimum voltage for long lithium life is below what lead needs to fully charge. Also contravenes ABYC and ISO standards to mix chemistries.I thought you just ran the lithium bank at a slightly lower voltage than optimum, and that this was the way hybrid lithium worked? The lead-acid batteries get 100% charged, the lithium ones never do but they last longer because of it?