Do I need an alternator protection device when switching to Lithium?

[senormechanico]

Originally Posted by john61ct

As a side note, I have yet to find an LFP mode I would use on a bank I care about.

The key attribute for a LFP charge source IMO is user-custom adjustable setpoints, not just a menu of "canned" predefined choices.

John, you remind me of a true story from the 1970's when as an electronics repair tech, I told a new customer his black and white portable TV was not worth fixing. He was a well dressed guy, and I offered him a deal on a new Zenith color portable. He said (and this is a direct quote I'll never forget),

"No thanks, I'm waiting for 3D color TV."


I assured him that even though the new set was a good one and he'd get many years of satisfaction of ownership from it, he'd almost certainly be ready for another TV by the time 3D came out. He was surprised by my comment, and purchased the new TV.


So, John, just jump in to the pool of LiFePo4 ownership. The water's fine.

[Stu Jackson]

Originally Posted by Oceanride007

--Quote (Originally by Oceanride007)---
>>>>>>>>>>>

.........but thinking I may be able to *run a small charger thru a inverter* from LA, if I want more or the other way around.

>>>>>>>>>>>>>>>>>>>>>>>>
---End Quote---

>>>>>>>>>>>>>>>>>>>>>>>


And your issue is?

No issue, just thought that when I first read it because it was standalone with no explanation of using shorepower at the same time.


No issue, no problemo.

[StowawayJoe]

Originally Posted by john61ct

Simpler is better.



Just put a lead batt direct inline with alt output all the time, if that's Starter fine. What is "normal", a simple VSR closes the connection to House based on

Won't this overcharge the lead acid battery? Can you mix battery technologies on a common bus?

[Oceanride007]

A factory installed Alternator would be OK for charging a LA battery any size, but you can't have it connected to in common with LFP.



On charge the LFP will take more from the alternator and at slow revs alternator won't have adequate air flow to prevent the alternator from burning out. (Unless you go to clever Regulator).


On Discharge the LFP battery will be a higher voltage than the at rest LA battery and because the LA battery has losses, you will drain House battery thru the start battery.


Not sure a one way VSR is designed adequately, would want it to close the circuit at >13.2v sensed from LA battery, but stops current from going other way, needs charge limiting as well. Don't know if one is available. John61ct not been around for a while.

[CatNewBee]

You don't need one. Stock alternators just doing fine with LFP, I have 2x 80A Hitachi stock alternators with internal regulation on my 2 Yanmar 40Hp Engines, they are doing fine with the battery isolator FET splitter to charge the start batteries and yeld about 40A each to the 1000Ah massive LFP house battery without getting damaged now for the 3rd year.

But if you have spare money and dont trust the bank, you can buy fancy devices and add them to your alternator in the engine compartment.

There are many different ways to configure your charge system depending on your use profile. Just be consistent.