Community Forums

KMcCarthy · 02-14-2022, 02:39 PM

Hi, I am doing a conversion from Lead Acid batteries to LiFEPO. I purchased a new converter which is compatible with lithium batteries so I should be good there but I'm not sure about charging off of the alternator. I have a 2018 Winnebago Intent with Ford E-450 chassis. Has anyone done this? There are dc-dc converters but if unnecessary why install one. Thanks

PJStough · 02-14-2022, 02:42 PM

Without a DC to DC charger and your LiFE PO4 battery is low enough the alternator will overheat and could be damaged by charging your battery at or near the full capacity of the alternator.

CRV2 · 02-14-2022, 02:51 PM

Also, your alternator's voltage regulator is not optimal for charging LifePo4 battery(s). ~CA

Biljol · 02-14-2022, 06:52 PM

I use a magnum smart battery combiner works well. No it will not get my lithium to 100% when driving but I don’t need it to.

I disconnected all other combiner but left the big boy on the switch if I need to charge the chassis fast.

I also converted my chassis battery’s to AGM the charge profile is so close they all are happy.

dssl · 02-14-2022, 08:13 PM

Quote:

Originally Posted by KMcCarthy

Hi, I am doing a conversion from Lead Acid batteries to LiFEPO. I purchased a new converter which is compatible with lithium batteries so I should be good there but I'm not sure about charging off of the alternator. I have a 2018 Winnebago Intent with Ford E-450 chassis. Has anyone done this? There are dc-dc converters but if unnecessary why install one. Thanks

You should get a shunt based battery monitor. This will allow you to accurately measure the current in and out of the batteries. It will also allow you to more accurately track your state of charge which is more difficult to track based on voltages with lithium batteries.

Once you have a battery monitor you can see how much current your alternator is pulling when your batteries are at a low state of charge which be the maximumcurrent. . The amount of current will depend on your batteries and alternator. If the current pull is less then 25% of the alternator capacity then you don't need to do anything, although a dc to dc charger will allow you to fully charge your batteries, which the alternator won't quite be able to do.

If your batteries pull more then 25% of your alternator rating then you need to disable your normal merge function and add either a DC to DC charger or an LBIM.