24 volt, 800 ah house bank for sailboat

[helmsmatt]

I’m about to pull the trigger on buying a 24 v 800 ah house bank for our sailboat.
I’ve already addressed the programming and protection for battery chargers, alternator, solar charge controllers, fusing and switching.

Two questions,
- should I go with 4, 24 v 200 ah batteries, or 4, 12 v 400 ah batteries?
- I’m buying in Europe. The decent quality sellers who ship in Europe are LiTime, Redodo, and Powerqueen ( I’m only pursuing brands that I can find positive test and tear down videos on YouTube).
Which seller has the best customer service and will be around to service their warranty?

I’m leaning towards 24 v 200 ah batteries for their highest combined discharge rate and ease of balancing, but my mind is open to alternatives.
Thanks in advance.

 

[Ampster]

In addition to the above criteria, one other factor would be the size of available space, weight distribution and the size of the units themselves.

 

[helmsmatt]

In addition to the above criteria, one other factor would be the size of available space, weight distribution and the size of the units themselves.

Thanks for the reply. I’m replacing 8D Gels that are a hair bigger than the LiFeO4s. The gels also weigh almost twice as much. So space and weight are not an issue, thank goodness.

 

[Ampster]

So space and weight are not an issue, thank goodness.

And, presumably, the gels were placed low and near the center which is important in a sailboat.

 

[time2roll]

Definitely 24 volt so the internal BMS can keep the full series string of cells in balance.

 

[helmsmatt]

Definitely 24 volt so the internal BMS can keep the full series string of cells in balance.

A 2S2P arrangement wouldn’t balance correctly?

 

[time2roll]

The series batteries could get out of balance and would need to be charged in parallel at the install to at least start balanced.
Of course a balancer could be added to manage that too.

 

[helmsmatt]

The series batteries could get out of balance and would need to be charged in parallel at the install to at least start balanced.
Of course a balancer could be added to manage that too.

That means I would have to initially charge with a 12 volt charger? Might be a problem.

 

[helmsmatt]

And, presumably, the gels were placed low and near the center which is important in a sailboat.

Battery compartment is centered right over the keel. Also forced air ventilated. Good design.

 

[Ampster]

Battery compartment is centered right over the keel. Also forced air ventilated. Good design.

I wish Lithium batteries had been around when I was actively cruising. That was so long ago, we only had Loran for navigation. The FLA batteries were right under my quarter berth and I guess breathing the Hydrogen gas probably did not hurt me but I often wondered how much acid fumes were also coming up from there. LEDs would have made the batteries last a lot longer too.

 

[hwse]

Thanks for the reply. I’m replacing 8D Gels that are a hair bigger than the LiFeO4s. The gels also weigh almost twice as much. So space and weight are not an issue, thank goodness.

These packs are 230Ah @ 24v in an 8D format.

Basen 24V 230ah Rechargeable lithium Iron Phosphate Battery pack - Basengreen | CATL LiFePO4 | Battery pack | Fast delivery

Basen 24V 230ah Rechargeable lithium Iron Phosphate Battery pack HOUSING: ABS CASE SIZE:522*240*218mm BMS: 150A BMS WEIGHT: APPROX. 38KG TERMINAL: M8 CYCLE LIFE: 5000+ WARRANTY: 5 YEARS...

www.basengreen.com

 

[helmsmatt]

These packs are 230Ah @ 24v in an 8D format.

Basen 24V 230ah Rechargeable lithium Iron Phosphate Battery pack - Basengreen | CATL LiFePO4 | Battery pack | Fast delivery

Basen 24V 230ah Rechargeable lithium Iron Phosphate Battery pack HOUSING: ABS CASE SIZE:522*240*218mm BMS: 150A BMS WEIGHT: APPROX. 38KG TERMINAL: M8 CYCLE LIFE: 5000+ WARRANTY: 5 YEARS...

www.basengreen.com

Thanks! Coincidentally, I found these just a few hours ago. I have a message into them. Seems this battery isn’t stocked in their France warehouse. I would opt for the bigger BMS and Bluetooth. Price seems very good. I checked some readin teardown and test videos. Very impressive.

 

[hwse]

I have two of the 460Ah @ 12v packs from them. I ordered them for delivery on the slow boat from China on 10/25 and they arrived in Arizona on 12/27.

 

[audiobill5]

Try Chargex in Tampa, FL?