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

[newhaul]

Originally Posted by Simi 60

That 40 litre engel is about the same price as our 240v 2 door 550 litre fridge freezer

We'd need 13.7 engels to match the internal space

Which do you think uses more power on a/litre of cooling basis?

Except most of us don't have your room so we get by with we have room for .

My system will be approximately 1.5cf freezer and 3.5cf spillover refrigerator .
I am considering having the divider adjustable to give me a larger freezer as needed I don't use much refrigerator space for much more than my beverages, cheese and eggs.

[Simi 60]

Originally Posted by newhaul

Except most of us don't have your room so we get by with we have room for .

Of course
Just saying for my way of thinking 12v refrigeration is bloody expensive and not very efficient on a / litre price and power usage.

Even on smaller boats who may have say, 3 Engels I reckon an off the shelf home style refrigerator , bigger battery and inverter works out cheaper.

[newhaul]

Originally Posted by Simi 60

Of course
Just saying for my way of thinking 12v refrigeration is bloody expensive and not very efficient on a / litre price and power usage.

Even on smaller boats who may have say, 3 Engels I reckon an off the shelf home style refrigerator , bigger battery and inverter works out cheaper.

Actually for my technautics system thev12 volt is a lower power draw as most of it is done during the afternoon when my bank is full and the solar is producing more power than I need . the dorm fridge setup uses almost as much ah as the last cool blue I had installed just to keep the inverter turned on .

[StoneCrab]

Boy that is a lot of pages of forum posts...
I haven't read them all, but I need to replace my batteries. It seems there is no magic bullet.

I would like to know if anyone uses Dakota Lithium Batteries.
https://dakotalithium.com/product/da...cycle-battery/

This battery is quoted at 277 amp hours and is in an ideal case size, which I can't quite get my head around based on the sizes of 100 ah and 200 ah batteries. It seems too small. From a price standpoint, the 277 ah is in line with prices of multiples of the smaller batteries.

Can anyone give me feedback on their experience with Dakota Batteries?

[Oceanride007]

I know Jedi has got a thread going "Cheap BMS ABYC Compliant"https://www.cruisersforum.com/forums...nt-269664.html
But I'm in Aus and I have My insurance demanding that my LFP battery be Aus/NZ standard. In particular:
(e) The battery shall be automatically disconnected by the BMS from all connected load and
all charging sources when temperature exceeds the manufacturer’s specified maximum.
(f) The BMS shall provide an audible and visual alarm at the normal vessel operating
position before a disconnection event occurs.
Can any one advise of a BMS that could do this. Thanks in advance.

[fxykty]

Originally Posted by Oceanride007

I know Jedi has got a thread going "Cheap BMS ABYC Compliant"https://www.cruisersforum.com/forums...nt-269664.html

But I'm in Aus and I have My insurance demanding that my LFP battery be Aus/NZ standard. In particular:

(e) The battery shall be automatically disconnected by the BMS from all connected load and

all charging sources when temperature exceeds the manufacturer’s specified maximum.

(f) The BMS shall provide an audible and visual alarm at the normal vessel operating

position before a disconnection event occurs.

Can any one advise of a BMS that could do this. Thanks in advance.

Tao BMS does. https://www.taoperf.com/ (the website requires you to register to view content). Here’s a comparison chart of five external BMS that are known to have external switching and advanced warning capabilities: https://www.taoperf.com/2022/10/30/b...parison-chart/.

[Simi 60]

Originally Posted by Oceanride007

But I'm in Aus and I have My insurance demanding that my LFP battery be Aus/NZ standard. In particular:
.

Let me guess, Pants?
And just what is this Aus/NZ standard they talk of?
Do they even know?

[newhaul]

Originally Posted by Oceanride007

I know Jedi has got a thread going "Cheap BMS ABYC Compliant"https://www.cruisersforum.com/forums...nt-269664.html
But I'm in Aus and I have My insurance demanding that my LFP battery be Aus/NZ standard. In particular:
(e) The battery shall be automatically disconnected by the BMS from all connected load and
all charging sources when temperature exceeds the manufacturer’s specified maximum.
(f) The BMS shall provide an audible and visual alarm at the normal vessel operating
position before a disconnection event occurs.
Can any one advise of a BMS that could do this. Thanks in advance.

That is a rather open to interpretation regulation . As each manufacturer can set its own temperature range to operate . Or is it disconnect on minimum temperature which for lifepo4 is 0°C or lifeypo4 which iirc is -4°C for charging .

[Oceanride007]

Should have added this. Attachment attached. First they referred me to the standard but it would have cost a boat buck to get it.
Think when ABYC add a amendment they always give a lead time or Grandfathering. I think they should do here, I will ask. I can't do anything inside 3 months as am required elsewhere.

Yes it is Pants, I suspect someone shooting from the hip as a result of a House Bank LA battery, and also house fires due to toys being charged, perhaps with a blanket over them.

[wholybee]

Originally Posted by Oceanride007

I know Jedi has got a thread going "Cheap BMS ABYC Compliant"https://www.cruisersforum.com/forums...nt-269664.html
But I'm in Aus and I have My insurance demanding that my LFP battery be Aus/NZ standard. In particular:
(e) The battery shall be automatically disconnected by the BMS from all connected load and
all charging sources when temperature exceeds the manufacturer’s specified maximum.
(f) The BMS shall provide an audible and visual alarm at the normal vessel operating
position before a disconnection event occurs.
Can any one advise of a BMS that could do this. Thanks in advance.

All of these requirements mirror ABYC. The cheap Daly BMSs that Jedi refers to in his post can be ordered with temperature sensors. Google it, check Amazon, or wherever. The BMS disconnects the battery, that is its job. Jedi's thread provides a way to have an alarm that goes off before the disconnect happens.
Jedi's thread is probably the cheapest route to a compliant BMS installation.

[wholybee]

Originally Posted by fxykty

Tao BMS does. https://www.taoperf.com/ (the website requires you to register to view content). Here’s a comparison chart of five external BMS that are known to have external switching and advanced warning capabilities: https://www.taoperf.com/2022/10/30/b...parison-chart/.

The Tao BMS is like the Lamborghini of BMS's. Technically, its everything someone might want. But holy #$% it is expensive. It's pretty hard for me to recommend a BMS that costs substantially (in some cases more than 2x) more than the batteries it is protecting.

[Simi 60]

Originally Posted by Oceanride007

Should have added this. Attachment attached. First they referred me to the standard but it would have cost a boat buck to get it.
Think when ABYC add a amendment they always give a lead time or Grandfathering. I think they should do here, I will ask. I can't do anything inside 3 months as am required elsewhere.

Yes it is Pants, I suspect someone shooting from the hip as a result of a House Bank LA battery, and also house fires due to toys being charged, perhaps with a blanket over them.

Well, our Lifepo4 system does everything the standards ask except this

(f) The BMS shall provide an audible and visual alarm at the normal vessel operating
position before a disconnection event occurs

BUT, the Victron battery monitor we had with the old AGM bank is set to provide an audible and visual alarm well below the BMS voltage or temp disconnect

[bill good]

OK I have to ask - Requirement for audio & visual indications for NORMAL OPS?? The Volt meter shows normal & would cover the visual "alarm" ?


What would a NORMAL audio alarm sound like?


Hooked up 800W of solar & seeing 50A into the 300A/H lifepo4 battery with 3000W inverter/charger. Disconnected shore power!


Regards Bill G

[wholybee]

Originally Posted by Simi 60

Well, our Lifepo4 system does everything the standards ask except this



BUT, the Victron battery monitor we had with the old AGM bank is set to provide an audible and visual alarm well below the BMS voltage or temp disconnect

Which provides no warning of a cell level over or undervoltage issue. I am perfectly happy using a victron battery monitor, but it is not acceptable according to the standard because it only monitors the complete battery, not cells.

[hjohnson]

Originally Posted by wholybee

All of these requirements mirror ABYC. The cheap Daly BMSs that Jedi refers to in his post can be ordered with temperature sensors. Google it, check Amazon, or wherever. The BMS disconnects the battery, that is its job. Jedi's thread provides a way to have an alarm that goes off before the disconnect happens.
Jedi's thread is probably the cheapest route to a compliant BMS installation.

I would argue that the job of a BMS is to control your charge sources and loads so that a disconnect will never occur. My BMS sets the voltage and current limits which are in turn used by my alternator, MPPTs, and Inverter/Charger.