Should I Use a Battery Isolator When I Am Charging Lithium Batteries With My Boat’s Alternator?

[@SoaringEaglesMountainBiking]

Hi Jeff love or videos. I have 400 ah of lithium and a LA start battery. The alternator is connected to the LA. The LA is connected to the Lithium by a dc to dc 12/30 charger. I had a 12/60 but changed it because I think the alt was working to hard on occasions. I have a 100 amp Balmar alternator with an APM. I run 2 bus bars one for the start battery and windlass and the second is the house bank and all solar goes to this bus bar and the house loads and inverter are connected to this one. Cheers Tom

[@reinhardfredebold9169]

Hello Jeff, thanks for your work. On my 50ft Narrowboat in the UK I have one Alternator (90A normal) and 100Wp solar on the 100Ah lead acid starter battery. 2 x 100A Lithium 12V parallel with 2 100A BMS and two DC/DC loader with MPPT (Renogy 30A each). Each takes up to 15A from the Starterbatery while the Voltage of the Alternater is higher than 13,2V. 2 x 300Wp Solar are connected to the DC/DCs. There is no possibility for the BMS to kill the alternator. There is a battery-switch in the engine bay on the minus of the starter battery for the event if the starter solenoid will fale. Whenever the alternator becomes warm, it delivers maximum 50A. Nothing is switched, everything is fused. This is enough for this boat.😊

[@AJM3201]

Hi Jeff, I'm a big fan and have watched most of your videos! In this particular video you might be spreading misinformation. The Victron battery that was shown has a BMS that is capable of controlling the charging input and load output separately. In addition, Victron has a module "SolidSwitch 104" which is capable of shutting down the alternator output by cutting the ignition switch circuit. A "Drop in" lithium battery does not have the same level of control.

[@jessefalsone1247]

All charging sources directly to LiFePO4 with smart regulation / appropriate programming, then DC-DC Charger to start battery. Works exceptionally well. One other point here. I used a 1/2/off switch (not both) for my start battery to allow me to start my 4 cyl Westerbeke from the house lithium bank in an emergency. The draw is less than 200A and is very transient. Battery manufacturer said this was fine. This goes against "conventional" lithium battery wisdom.

[@BingoDingo-nv3gk]

Jeff forgot mention the DC to DC is a Victron non isolated also on a lip04 profile cheer Al

[@RealGrubert]

I am installing Litium house batteries and an Enersys TPPL start battery. The Lithium is 4 x Dakota 200Ah 12VDC jars. I will charge the house batteries with the alternator through a regulator (that can be programmed for my lithiums) and connect the house and start battery banks via a Blue Sea Automatic Charge Relay. I would never treat a lithium the same as a lead acid battery, they are very different animals.

[@Skits_Missions]

It’s not hard. I have full lithium, hybrid start lithium and Victron DCDC to house. Running great for over 12 months.

[@stephenburnage7687]

Is there a preferred / recommended lithium solution for a small (34 ft) sail boat? AYBC seems to simply say "follow manufacturers recommendations' but battery/alternator recommendations all seem to differ. For instance, been in contact with Marine Pro (my smart charger) and they clearly say that they recommend against a mixed lithium and lead acid system. Also, can I ask, do automatic combiners (where the house + start combine under low or high voltage conditions) need to be removed in these set ups?

[@swimmer56]

You have been producing great videos for years and I really appreciate them, especially the longer ones showing your classes. I was wondering if you are charging directly to the lithium house bank from the alternator and using a DC to DC charger to the start battery (AGM or lead acid), if the house bank cuts off, there is still the DC to DC charger taking some of the load. Is it that if the start battery is fully charged and on float, the load dump, could be to high? There should always be some load through the DC to DC charger to the start even if it is fully charged no?

[@darylclark8906]

Jeff, could you comment on the BALMAR APM (Alternator Protection Device) as a solution for connecting the ALTERNATOR directly to the LITHIUM BANK and charging the AGM STARTING battery using a DC-DC Charger?

[@deniz-akkaya-x]

Thanks Jeff, do I still need a regulator after the battery isolater in order to charge my lithium house battery? And also second question, if lithium house battery is off via bms, usually alternator is also connected to the engine battery. In such scenario, do I still need an isolater?

[@SailingTalisman]

Question Jeff: Is a battery isolator doing the same thing as an APD, or Alternator Protection Device? Examples being Sterling Power 12V APD12 and 24V APD24, or the Balmar APM12 and APM24.

[@BingoDingo-nv3gk]

Hey Jeff I have a curious situation on my boat lip04 house, lead acid start ,with DC to DC charger with Balmar external regulator plugged into shore power it will charge to 100% but cast off the lines and it won't maintain a full charge underway, my charger has a lip04 profile the Balmar has a lip04 profile the Magnum charger has a. lip04 profile and I have 4 175Amp lip04 batteries in parallel which has a BMS when underway to and from Alaska last summer it only full charged the house bank just 1 time. It would be nice to have a full charge when dropping the anchor. There has to be a conflict here somewhere any ideas or suggestions would be greatly appreciated, Cheers Al

[@darylclark8906]

BALMAR has an ALTERNATOR PROTECTION device called the APM - speaking with their TECH SUPPORT: this device (APM) will protect the ALTERNATOR from LITHIUM BATTERY BMS shutdown. It will au;tomatically reset itself after protection occurs.

[@akajbssmith7423]

I currently run my marine AC system (FCF 5K BTU) using a Xantrex inverter while underway. Power is older F225 with I believe a 45a output. My battery switch is a BEP Cluster switch with the VSR function. My current start battery is the Optima Blue top and the house is a Vmaxtank 200ah AGM. I’ve been running this system about 6 years and my AGM’s are due to be replaced in the spring. My concerns are a few. Do I need to do anything special to my set up charge the Lithium with the outboard. I would also like to just go Lithium for the start as well. My shore power charger is a ProMariner 1220P with the Lithium settings so I’m not as concerned with that side of charging. I appreciate any help I can get with this. Tks

[@alfredochiappini1056]

What happens if you do turn off the alternator switch before you start the engine? Where does the alternator put its power?

[@oneeyedjackass]

I have house, starting & thruster batteries (all lithium) connected to argofet (outputs 1, 2, 3) with alternator connected to input. Should my 120V shore charger be also connected to argofet input or directly to house battery?

[@user-jz8tc8yh4p]

Hi Jeff, First great videos!! What happens to the charging profile while using a battery isolator? I assume you would want to set the external regulator to lithium however can the starting battery handle this profile in the log run? Thanks! Steve

[@thehopulusexperience995]

Hi Jeff, great video. I have a question which might interest others: can I connect two alternators to the single input post of my victron agrofet? And further where to I connect the voltage sense wire? House bank or one of the two engine batteries?

[@alfredochiappini1056]

Only one isolator per alternator

[@juliehoule8183]

Argofet