Lithium/lead acid hybrid system

[Diesel Pro]

Credit to bobcoy for sharing this with me.

https://www.zwerfcat.nl/en/lithium-hybrid.html



My initial thought of mixing the 2 technologies was that the lithium would just deplete itself trying to charge the lead acid battery, but it seems it would be more of a constant "soft trickle" charge. At one time I had considered adding something like a 20ah lithium at the helm. I figured I would need to get creative with diodes or isolators to prevent discharge to the starting battery while allowing charge, but that seems to not be the case. This should also eliminate any BMS voltage reset issues with certain outboard charging systems using lithium. This would also be a great way to perk up the voltage for Humminbird and their stupid low supply issues and still have plenty of reserve to start the main if you ever run down the lithium. Fast charging recovery on the run.

If I had room and had it to do over again and had the space I’d consider sticking with AGM starting and adding something like a 50ah lithium.

[Sleepy111]

That is an interesting read. I have an AGM as my cranking battery per mercury specs and I also have a separate lithium dedicated just for my electronics so it is not connected to the motor at all so anytime on the water it is not being charged or maintained by the alternator. Seeing how I am running 4 screens and livescope I did not want to take the chance of killing the cranking battery on a full days trip with it running everything else in the boat plus all the electronics. On a normal day on the water with all 4 screens and livescope running I use an average of about 40% of the lithium. It gets recharged by a separate charger also so it is totally independent........for now. I am going to get me a set of battery cables tomorrow and connect my AGM and lithium up and see how it does on my trip to the lake Friday.

[Diesel Pro]

Anxious to hear your results. I went with a 125ah Ionic starting battery so really no going back now. I'm just trying to work myself out of the charge fully before storage mentality. The starting battery hangs in at 90%+. My 100ah trolers finish in the middle somewhere depending on the use. In your case I might consider not shore charging the lithium at all. Instead of cycling 100-60-100 might try say 80-40-80. Of course alternator charge will dictate the high number.

[lauzon4]

Same here, I’m very interested in how this works out. Sleepy, what batteries are you running now?

[Sleepy111]

I have a Deka AGM for the cranking that came in the boat and added an ionic 125ah lithium just in March for electronics. Trollers are still Deka group 27 deep cycles that came in the boat. Haven’t changed those to lithium yet, going to wait and get a little more time out of them first since they are only 1 yr old. When I do change them I will be putting 100ah Ionic’s in their place.

[lauzon4]

I have a Deka AGM for the cranking that came in the boat and added an ionic 125ah lithium just in March for electronics. Trollers are still Deka group 27 deep cycles that came in the boat. Haven’t changed those to lithium yet, going to wait and get a little more time out of them first since they are only 1 yr old. When I do change them I will be putting 100ah Ionic’s in their place.

Thank you. Let us know how it turns out

[cevans]

If you have a standard wet cell hooked up parallel to a lithium battery and hook a Lithium charger to the lithium battery to charge would the lithium charger charge the wet cell also when in parallel?

[Hooked247]

Check out Chris Zaldain's new Skeeter video on YouTube, that's how his boat is rigged up. He has three Battle Born lithiums for his trolling motor, and what appeared to be an Odyssey AGM with another smaller Battle Born lithium connected to his AGM.

[cevans]

I can see a agm charger charging a lithium and agm in parallel as that is the type charger I use set to agm setting. But questioned if the charger attached to the lithium of which would possibly be hooked to a standard wet cell in parallel, would charge both when a lithium/wet cell is hooked parallel? I don’t think the charger would charge a standard wet cell but thought maybe someone out there would have the answer.

[Diesel Pro]

If you have a standard wet cell hooked up parallel to a lithium battery and hook a Lithium charger to the lithium battery to charge would the lithium charger charge the wet cell also when in parallel?

I would go AGM/lithium. I would suggest you read the article that I linked.

[mkm]

My setup is agm for cranking (mercury 4 stroke), Ionic 100ah for powering the rest of the boat (grounds are connected on these two). Also have 2 Ionic 100ah for trolling along with the Ionic charger. Been working great. No more power problems with electronics.

[Ann-Marie]

Yandina now has a Lithium version of their battery Combiner that will isolate the Lithium from the lead-acid starting battery when not charging so the Lithium won't discharge itself into the lower voltage lead-acid battery.

[Diesel Pro]

Yandina now has a Lithium version of their battery Combiner that will isolate the Lithium from the lead-acid starting battery when not charging so the Lithium won't discharge itself into the lower voltage lead-acid battery.

That's a great idea, but I'm not so sure it's necessary. I've rethought my views on this after reading that article and I think having the lithium as a battery maintainer for the conventional battery would be a good thing for both batteries.

[rockmike]

I run an AGM-Lithium with a Yandina Combiner. Works good for me.

[BBW]

i have a 10/2 run from my agm starting battery to storage compartment in front of console to a blue ray fuse panel, i have my network box,panoptics black box,nema 2000,and steady cast all mounted in that storage. i been thinking about adding a lithium for electronics if i do i am putting the lithium battery in the storage box and connect both batteries to a 4 position perko switch. i figured if i switch to both batteries while running it would charge the lithium from the motor. i think that would work only thing i not sure the motor would charge the lithium. any one tried this

[Diesel Pro]

I would just connect the 2 batteries in paralell and try that first. Not really an APP type guy, but the Ionic app is really handy to know state of charge status as well as current rate of charge/discharge. Everything should work automatically. If yoiu have issues then try a fancy switch, but then you have to remember to change selection.

[Lou r Pitcher]

Interesting that the author of the article fails to mention the added stresses to an alternator/voltage regulator and the additional heat that must be successfully dissipated as a result of the lower resistance of a fully discharged Lithium Ion/fully discharged Lead Acid AGM configured in parallel.

[lauzon4]

So has anyone on here actually tried this or know someone that has?

[Diesel Pro]

Interesting that the author of the article fails to mention the added stresses to an alternator/voltage regulator and the additional heat that must be successfully dissipated as a result of the lower resistance of a fully discharged Lithium Ion/fully discharged Lead Acid AGM configured in parallel.

Two things I see here:

1) Most do not fully deplete even their LI batteries if properly sized. In a hybrid system the lead acid typically should not cycle to much depth if at all.

2) Many running just LI batteries so any charging system issues should show there and we've not seen any reports

3) Merc voltage regulators are water cooled on many or most models.

I'll be the first to agree that an alternator is not really meant to be a battery charger so much as a battery maintainer, but most boaters also are not taking long trips with highly discharged or failing batteries. Even then, they recover pretty quickly.

[John Jackson]

I'm waiting for someone to try the lithium AGM combo themselves, instead of telling others to try something like this without experience to back it up.
Who wants to be the first to try it, and give an occasional report of performance and issues?????