Building my first LiFePO4 battery bank for a caravan

[grey nomad]

Hi to all the DIY solar enthusiasts
I was originally planning on building 12v 200ah bank using 2 12v 100ah batteries in parallel.
They would be used in my caravan to travel off the grid around Australia.
After reading through this very informative forum, i noticed the great deals with Xuba seller on Alibaba for 280ah cells.
The extra capacity would be useful but was thinking i would like to have 2 batteries, one for redundancy.
I would have trouble fitting 2* 12v 280ah batteries in the van and the cost would be out of my budget.
The redundancy would be good for my essential load of 2 small 12v fridges drawing 15A total
No inverter so nominal load would be around 20A and max load around 50A for the air compressor used with my airbag suspension.

Pro's i see with a single 280ah battery are.
Cheaper cost per AH
1 BMS
Less wiring.
No problem with internal resistance miss matching developing with parallel connected batteries.

Con's
No redundancy.

My setup is
450w solar
30A Redarc mppt solar controller,
30A dc to dc buck boost charger from car.

Just looking for any suggesting of what other people have used or setup.
How common are failures with Lithium.
My only experience is with lead acid batteries and have had no problems except the 50% DOD usable capacity of AGM batteries.

 

[Chris61]

Hi Grey Nomad, my 8 x 200ah cells arrived today from RJ Energy. I was very impressed with the email chat with them. I performed a few dummy bookings for different sized batteries. I made payment with Paypal, there was a surcharge. Approx $AU1.43 for every US dollar and don't forget GST. Tracking of my package was fantastic. I was able to see ship dock in Sydney, as well as Star Track Express delivery to my door in Penguin Tasmania

 

[grey nomad]

Hi Chris
I will check out RJ energy. How much was the freight and what form of transport did you use.
Seem like a lot of people like the suppler called Xuba on Alibaba.
Did someone recommend RJ energy.
RU building 2 *12v batteries or 24v.
What BMS will you be using.
Thanks
Emmanuel

 

[Ample]

I concur with you on the redundancy issue. While I hope to one day roam the Outback, I intend to roam N. America. And to remote places too where a battery failure would be very inconvenient (to put it mildly). As a former techo-nerd, redundancy is a big deal.

Due to the incredible value (cost per Ah) of the 280Ah battery builds that people here are doing, I was heavily contemplating building one or maybe 2 of those myself.

But just like you, I saw that the cost would be higher and there are the size and weight issues. I have a large cargo van but the smaller size of a 100Ah battery would allow me to fit it 2 or even 3 batteries into a fairly small space.

Another "plus" is higher current in a multi-battery parallel bank. If you use 100A BMSes in your 100Ah batteries, then with 2 batteries in parallel, you'd get 200A of continuous power. That could be awesome if you need it. For example, I will be able to run my induction burner at full power (1800W) whereas with the single 100Ah battery I have now, I set my burner to 60%. The single BMS of just one 280Ah better will give you a similar continuous power limitation.

 

[Chris61]

For 8 x 3.2V 202Ah battery, USD115 per unit, sub total is USD920.
For 14 x copper connector, USD2 per piece, sub total is USD28.

Shipping fee to door by sea: USD255 Shipping time: 25-35 days

Sub total is USD1,203. Paypal have a 5% surcharge. Money deducted from my account, $AU1890.29
Figures above just give you an idea of exchange rate, Paypal charges, GST.

Purchased 9th June, arrived 15th July, can't complain about that

Consignment: 7RFZ50027483
Service: Express
Despatch Depot: Shekou Pt, China
Despatch Date: 20/06/2020
Delivery Depot: AU
Status: Delivered
Last Scan: 15/07/2020 11:36:00

Date & Time​	Description​	Depot​
10/06/2020 16:23:06	Shipment info received
20/06/2020 00:00:00	Sea vessel dispatched HARRIER HUNTER/2004S	Shekou Pt, China
29/06/2020 12:41:27	Shipment info confirmed
30/06/2020 17:06:13	Customs held	Kingsgrove
03/07/2020 13:18:08	Clearance processing complete	Kingsgrove
04/07/2020 00:00:00	Sea arrived HARRIER HUNTER/2004S	Sydney, Australia
09/07/2020 19:31:46	Deconsolidation has been done, waiting for despatch
10/07/2020 13:08:39	In transit
10/07/2020 15:48:33	Shipment despatched to courier
15/07/2020 04:47:00	2 items On Board for Delivery	DVP
15/07/2020 11:36:00	2 of 2 Delivered	DVP

StarTrack: 7RFZ50027483

 

[sharpey]

I got the xuba cells... so far very pleased with them... they are well matched. Cost the equivalent of AUD$1443 to get them airfreighted to Singapore...

 

[Pierre]

For 8 x 3.2V 202Ah battery, USD115 per unit, sub total is USD920.
For 14 x copper connector, USD2 per piece, sub total is USD28.

Shipping fee to door by sea: USD255 Shipping time: 25-35 days

Sub total is USD1,203. Paypal have a 5% surcharge. Money deducted from my account, $AU1890.29
Figures above just give you an idea of exchange rate, Paypal charges, GST.

Purchased 9th June, arrived 15th July, can't complain about that

Consignment: 7RFZ50027483
Service: Express
Despatch Depot: Shekou Pt, China
Despatch Date: 20/06/2020
Delivery Depot: AU
Status: Delivered
Last Scan: 15/07/2020 11:36:00

Date & Time​	Description​	Depot​
10/06/2020 16:23:06	Shipment info received
20/06/2020 00:00:00	Sea vessel dispatched HARRIER HUNTER/2004S	Shekou Pt, China
29/06/2020 12:41:27	Shipment info confirmed
30/06/2020 17:06:13	Customs held	Kingsgrove
03/07/2020 13:18:08	Clearance processing complete	Kingsgrove
04/07/2020 00:00:00	Sea arrived HARRIER HUNTER/2004S	Sydney, Australia
09/07/2020 19:31:46	Deconsolidation has been done, waiting for despatch
10/07/2020 13:08:39	In transit
10/07/2020 15:48:33	Shipment despatched to courier
15/07/2020 04:47:00	2 items On Board for Delivery	DVP
15/07/2020 11:36:00	2 of 2 Delivered	DVP

StarTrack: 7RFZ50027483

Hi Chris , that is impressive. The reason that the shipping costs are relatively high is that it was a DDP ( Delivered Duty Paid ). So no more hold ups at customs and clearance issues etc. I would advise any buyers to follow this route - check with the seller if it is a DDP purchase.

 

[Chris61]

Hi Chris
I will check out RJ energy. How much was the freight and what form of transport did you use.
Seem like a lot of people like the suppler called Xuba on Alibaba.
Did someone recommend RJ energy.
RU building 2 *12v batteries or 24v.
What BMS will you be using.
Thanks
Emmanuel

I am building a 400ah 12v system using a SBMS bms from Electrodacus
lots of different places to buy batteries. I tried a few dummy bookings with different suppliers.
Some were very vague, some were expensive with CALB and Winston cells, all were cheaper than Aussie prices.
I liked the correspondance with RJ Energy and the ability to pay with paypal, even with a surcharge

 

[Chris61]

 

[grey nomad]

Did RJ energy charge you GST or do you have to pay it at some stage through customs like people in the US and Canada have to.
The packing looks really good from RJ energy compared to XUBA packaging.
Considering one of the main complaints about Chinese supplied cells are damage in transit.
I will be considering the package quality in my decision on which supplier i will use.

 

[Chris61]

I was very impressed with packaging, 4 cells per box. 40mm of foam around 4 cells

GST was taken out with PayPal payment