LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

[john61ct]

Adding Guangzhou Fullriver

=============>>
known LFP prismatic cells, actual manufacturers, all from China:

CALB

Winston (as Thundersky OR Voltronix)

Sinopoly

A123

GBS

Lishen (apparently supplies Apple, Samsung, LG, HP, Dell and Lenova?)

[AKA-None]

Originally Posted by senormechanico

How about replacing that "relay that needs the constant drop to ground to open" with a bistable relay, i.e. pulse the winding to open, pulse to close
<snip>

That's called a latching relay.

[senormechanico]

Originally Posted by AKA-None

That's called a latching relay.

Whatever floats your boat...

Also called a Bistable Relay.

1. What is a bi-stable relay? - Kisi Help Center - Support
   
   
   https://support.getkisi.com/article/bistable-relay Proxy Highlight
   This is why it is called a bistable relay: the circuit is stable when it is both closed and open. The bi-stable relay is only present in the Kisi Basic Controller. Before ...
2. Bi-Stable Latching Relays - Littelfuse
   
   
   www.littelfuse.com/products/dc-solenoids-and-relays/b... Proxy Highlight
   littelfuse-relays-solenoids-bistable-latching-tl. Bi-Stable Latching Relays. Bi- stable or 'latching' solenoid/relays are stable in the On or Off position, requiring no ...
3. Bistable Relay Tester - ElectroSchematics
   
   
   Bistable Relay Tester Proxy Highlight
   Bistable relays (BR) are widely used in battery powered equipments or applications with “memory function”. No doubt, when it comes to an average electronic.
4. Relay - Wikipedia
   
   
   https://en.wikipedia.org/wiki/Relay Proxy Highlight
   A relay is an electrically operated switch. Many relays use an electromagnet to mechanically operate a switch, but other operating principles are also used, such ...
5. Bistable Relay - ABB Group
   
   
   https://library.e.abb.com/public/a5f5e2b3698dd1c86525... Proxy Highlight
   The bistable relays in the COMBIFLEX system, type. RXPSU6n and RXPSU14n are composed of the same constructional elements as the established.
6. Latching/Bistable Relay - Del City
   
   
   https://www.delcity.net/store/Latching-Relays/p_81811... Proxy Highlight
   A latching relay is a two-position electrically actuated switch. It is controlled by two momentary-acting switches or sensors. One sensor 'sets' the relay and the ...
7. Latching relay, bistable relay for heavy duty applications, by Mors ...
   
   
   www.morssmitt.com/industry/heavy-industry/industrial-... Proxy Highlight
   Eletromechanical latching / bistable relays for demanding, heavy duty applications such as power utilities, petro chemical industries and mining, by Mors Smitt.
8. Latching relay, bistable relay for general purpose applications, by ...
   
   
   www.morssmitt.com/industry/heavy-industry/general-pur... Proxy Highlight
   Latching relays. Pulse activated latching / bistable relay. For general purpose, industrial applications, switching of AC or low DC voltages / resistive loads.

9. Bistable relay circuit - YouTube

   
   
   
   

   https://www.youtube.com/watch?v=0tR5nwfENb4

   Proxy Highlight
   Aug 1, 2011 ... This circuit can be used to make bistable a normal relay. It works with 24 Volt power supply, but the relay coil is 12 Volts - 140ohm.
10. Series RB - Bistable relay 8 A | Finder
    
    
    https://www.findernet.com/en/worldwide/products/famil... Proxy Highlight
    Bistable relay. 2 or 4 pole changeover contact; DC voltage; 2 coil type; SET and RESET signals; 35 mm rail (EN 60715) mount; Pin socket type 90.21 mount.

[john61ct]

Wow lot of effort there! Lots of things have more than one name.

[alctel]

My 8x200AH cells just arrived apparently, picking them up this weekend.

Guess I actually need to decide on a BMS sooner rather than later! (and solar controller, charger and alt)

[senormechanico]

Originally Posted by john61ct

Wow lot of effort there! Lots of things have more than one name.

About 30 seconds from startpage.com doing a search for bistable relay.
Copy, paste, post, done.

[john61ct]

I meant to read it 8-)

[alctel]

Thoughts please on this

looking at getting the Promarine TruePower Combi 1500W

TruePower Combi 1500W QS - 110V AC/12V DC | ProMariner

Looking at the manual it says the charger has a custom setting, but I can't find reference to it anywhere else in the manual so I'm loathe to believe it exists.

However, one of the options is this:


Boost Charge Float Charge

AGM 14.1 13.4


I'd prefer a boost charge of 14.0, but there is any reason why this wouldn't work? The BMS would have the warning level set to 14.2 and the OH CRAP DISCONNECT level set to 14.4

There is also

Boost Charge Float Charge

AGM 14.0 13.7

But I think the float charge there is way too high.

Still looking for a charger that just straight up disconnects at 14...

It also doesn't have a dedicated voltage sensing wire, but this thing is going literally right over the batteries so I'm not that concerned.

[john61ct]

14.1V is a bit high, but shouldn't cost much longevity, you definitely want the lower float unless you're babysitting manually.

Try calling PM tech support re custom?

[alctel]

Originally Posted by john61ct

14.1V is a bit high, but shouldn't cost much longevity, you definitely want the lower float unless you're babysitting manually.

Try calling PM tech support re custom?

I've sent them an email - will see what they say. Thanks for the input on the charge voltages.

The other option I'm looking at is seperate charger/inverter namely

ProMariner 40 Amp ProNauticP 1240P Battery Charger (fully customisable)
Xantrex Pro Series XM 1800 Power Inverter

Which together should do the same thing as the combo unit (for around the same price). I can use a modified sine wave as I'd just be using the inverter for an electric hot water tank (sometimes), charging phone/laptop/drill and for boiling an electric kettle.

[john61ct]

Yes good charger, same as Sterling I believe. How big is your bank?

Xantrex CS attitude really sucks, they consider their low-end disposable if anything goes wrong.

I would consider either going with a better (more expensive, Victron, Magnum, maybe start a new REC thread) brand/line, or going for the real low-end, where you can feel OK about "disposable".

Personally I look for quality DC native devices, and if I **really** wanted something available in AC only, would buy an inverter for just that device, lower amps modified sine is so much cheaper than a big pure sine one.

[exMaggieDrum]

Originally Posted by toddedger

"Before you get too far into a BMS design for marine Li systems, you might want to wait until the new ABYC Standards come out for lithium and high-capacity batteries. It is a slow process, but it's getting closer to fruition. A good number of very experienced Li battery players are involved.

It's possible that once the Standards are out, boats adding DIY Li systems might have difficulty getting insurance unless they carefully follow the guidelines in the Standards"



I'd like to know who the good number of very experienced Li battery players are. Have they written any books on the subject? What kind of track record do they have? Or are they just declaring themselves experts so they can push their own outrageously expensive solutions. Has there been a rash of Li incidents that we need to get a handle on?

I have yet to see a turn key solution that is going to work for an owner who doesn't understand the technology. Watermakers don't do to well we people who don't understand them.

So by giving standards abyc will be legitimizing Li for a whole bunch of people that have that have no business being involved with it. From what I've seen, some of the most experienced Li people don't want to be involved with building systems for the masses.

Then on the other side of the coin, some commonsense rules might make it easier for the DIY guy to get insurance in the first place.

It's going to be really interesting to see what the "very experienced Li players" decide for us.

ABYC standards are primarily for the boat builders and trained techs who maintain and upgrade systems. They are not for the owner level except for those who really know that level of tech. All you have to do is look at even the "simple" AC sections of the standards to see how the vast majority of DIY owners would be blown away by trying to read, understand, and correctly apply the standards. Just this forum provides too many examples of DIYers who think they understand all they need to about safely rewiring their AC systems, and some of them claim to have read the standards.

The lithium standards will be primarily for the builders who will be putting in the systems and the techs who will work on them. Unfortunately, the uber-low-risk insurance underwriters can be clueless as to when and where you need to follow the standards to the Nth degree. The standards are only recommendations anyway and boat builders can ignore them or modify them as they see fit, even when claiming their boats meet the standards.

I see ABYC promulgating Li standards as a very good thing provided they do them "right" and the committees who write them don't negotiate them to the lowest common denominator.

The scariest issue is for surveyors who might be the most clueless but still don't want to admit it, write down a boat with Li onboard trying to apply the standards.

[alctel]

Originally Posted by john61ct

14.1V is a bit high, but shouldn't cost much longevity, you definitely want the lower float unless you're babysitting manually.

Try calling PM tech support re custom?

So they replied that it was a custom feature but it never got enabled.

So I guess the only option on that unit is the setting

Boost Charge Float Charge

AGM 14.1 13.4

rats

[exMaggieDrum]

I would go with separate units and install the ProNautic charger. I plan to get one as a backup to my older combi unit. I can live without the inverter part but not without the charger. And, small chargers can be had for charging the (essential??) computers and phones, etc. Heating a water tank can be very bad for batteries and the inverter. Usually not a good idea.

[alctel]

I'll probably go with the separate units.

I also wanted to power my kettle off the inverter, as I calculated 70% of my propane use was just boiling water!