AGM vs Lithium

[dhbret]

For charge controller/battery management systems that don't break the bank check out Bogart Engineering and also a fellow that goes by "Electrodacus". For the past 4 years, I been using a BMS from him for our off-grid LiFePO4 run cabin.
http://www.bogartengineering.com
http://electrodacus.com/

[John61CT]

Bogart's Trimetric is an excellent coulomb counting meter for pack level SoC, but does not do anything at the per-cell level

which is required to call a device a BMS.

Besides electrodacus, which is a bit inflexible, check out Chargery's, but really there are dozens / hundreds of BMSs out there at all price points.

[bdosborn]

There a hundreds of chinese BMS with no published specifications, highly exaggerated current ratings and no temperature sensing. Electrodacus seems promising but is sold by a guy out of his house, who knows how long he'll be around. I'm waiting for a big name like Victron or Trojan to come out with a BMS that is well engineered, has a solid warranty and doesn't cost more than $150.
Bruce

[John61CT]

That lot maximize their profits by selling expensive packaged systems through their dealer networks, not helping DIY types save money.

Thousands of users go without "a BMS", it's just a label for collections of various functionalities.

https://endless-sphere.com/forums/viewt ... p?t=104997

[Westley]

What about the Jackery power station or the Goal Zero?

https://www.amazon.com/Jackery-Portable ... 47&sr=8-16

[bdosborn]

I'd look at them pretty closely if I had a relatively small load (maybe a cell phone and some LED lights) and didn't want to mess with building a battery system. Irritating Will Prowse likes the Jackery, as well as some others on YouTube. They are a little spendy compared to what you build on your own but an Amazon warranty is a good thing.

Bruce

[Westley]

The Goal Zero Yeti is really expensive for my budget. The most amp draw for my rig, as planned, will be the overhead fan and a 12V frig. All lights are LED. I figure I can boondock for two nights without recharge, at least. I also have a Yamaha inverter generator to extend my stay if needed.

I'm pretty sure that I'm going with the lithium power pack, either the Jackery or Goal Zero, as much as I can afford. I plan the wiring accordingly. The one thing that appeals to me is that the unit also serves as a converter. It can run 12V stuff while charging plugged into AC shore power or the generator. And while running for the day, let the alternator charge it. As I read the product info, I believe it can run the DC frig while charging on either DC or AC.

[John61CT]

Those powerpacks are limited like drop-ins in charging C-rate and even more so in capacity

crapshoot if the sizing of included gizmos suits your use case

no idea who makes / what sort of quality / longevity of the cells

super expensive $ / Ah @12V

and they don't offer user replaceable cells.

For me, pass

[GPW]

Battery tech is evolving so fast now , I’m going to wait a bit too … And as we’ve already seen with so many other products , those high prices will come down with more production /popularity …

[Westley]

Okay, I "hear" you.

There is the Battle Born LiFePO4, which is expensive but probably as close to a sure thing available now in lithium.

As I understand, from some research, the converter/charger for AGM setup will not work with lithium setup.

So, if switched later, the whole system will need to be upgraded, including the solar controller if present.

If I'm not right or missed something, please correct me.

[tony.latham]

...the converter/charger for AGM setup will not work with lithium setup.

My solar charger and Noco charger have the options for AGM, FLA, and Lithium. Charging from the tow vehicle with a lithium battery is probably a big no-no without a DC to DC charger. And they aren't cheap.

Tony

[Westley]

Charging either the Jackery or the Goal Zero with the alternator of the tow vehicle is no big deal, as I understand it. Just plug it into a 12V socket, and unplug when driving is done.

I'm still researching. Found this so far: https://battlebornbatteries.com/charger ... ity-table/

Charger Compatibility Table

[John61CT]

I have yet to see a "lithium ready" setpoint I would allow to charge any LFP bank of mine.

All that is required is user-adjustability of the profile setpoints, that way you have the flexibility to adjust to circumstances in caring for the bank the way you want to.

Assuming optimal longevity is a goal.

[Westley]

Maybe it's no big deal or too expensive to convert to lithium from old style batteries.

Before purchase I'll dig deeper.

But here's an example of why I'm cautious and uncertain:

https://www.etrailer.com/RV-Converters/ ... 60ALV.html

In this link, note the Note: "Charge Wizard not compatible with lithium converter chargers.This converter charger converts AC shore power into DC power and charges your battery bank. The converter uses a higher voltage output to provide the proper charging profile for lithium batteries. If your RV already has a stock converter charger, it will need to be removed to ensure this unit operates properly."

Also, in the data per the link with etrailer.com:

Designed for Lithium Batteries
Built for lithium batteries, this unit uses a higher output voltage than a typical converter charger, which provides a fast, complete charge. The charger also extends battery life since it utilizes the appropriate charging profile. Additionally, it's compatible with your battery's internal Battery Management System (BMS), which helps manage charging by monitoring the battery state and balancing cell voltage.

[tony.latham]

Why would you need a $200 60 amp charger? Why not a $60 Noco with lithium settings?

Tony