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We have successfully negotiated a sale of our 2015 Jayco Silverline 25' Outback complete with it's 1200 w solar and 600 Ah LiFePO4 battery bank. This 3500kg + monster has been a great rig and has covered over 50,000 km and been our full time home for close to four years.
We now have a home base and have decided to downsize our van. Have organised a private import of an Elddis Supreme 860 from Preston Caravans in the UK. ($25k cheaper than I can purchase the same van in NZ) https://www.prestoncm.co.uk/product/supreme-860-2018/ It is an 8' wide van that I intend to raise the ride height by 100mm - fit larger wheels / tyres - install 800 Watts solar and fit these two - Two year old LiFePO4 150 AH batteries I just picked up for NZ$1750 for the pair. http://en.tianzepower.com/index.php?m=c ... =26&id=159 They are each assembled in a case. They have been sitting in storage for the last six months and all 8 cells have a static reading of 3.3 volts. I will be interested in your comments Terry. I have purchased a pair of fully customisable SRNE 40 Amp MPPT controllers and will configure my solar into two 400 w strings.
Lastly will be the installation of a 150 lt fresh and 150 lt grey water tanks, Topargee water meter and a 2000w PSW inverter.

Cheers
Chris

That new van will have great insulation for sure. Chris how long have you lived in Hastings?

I was born in Waipukurau and raised on the family sheep & cattle farm at Elsthorpe about 40 km from Hastings. Have lived permanently in either Havelock North or Hastings since 1988.

Cheers
Chris

Hi Chris, can you reconfigure the cells into 1 x 300Ah 12v battery rather than 2 x 150 Ah 12v batteries? If you can't you are going to face a world of problems. We are already seeing some who jumped at the drop in 100Ah batteries and connected 3 or 4 together in parallel, just like they had with their old lead acid batteries, are now selling those batteries and going to other resllers who are telling them what they want to hear. I'm sure it will only be a matter of 12mths or so before these same people are again crying on the forums that their lithium batteries aren't doing what the lithium people say they will ......

T1 Terry

Thanks Terry. I just knew that you were going to repeat the advice you gave me when I purchased 8 x 300AH cells back in January 2015 for the van we have just sold. I have them configured into four paralleled pairs making one big 600AH battery. I should be able to disassemble the existing packs and reconfigure them.
I have yet to get my hands on my new purchase as my brother collected them for me and has them in Auckland. We are currently holidaying in Twizel in The South Island and will not get my hands on them until mid May.

Cheers
Chris

Terry, would be interested in what the negative effects are running lifepo4 packs in parallel. When on the road, my 120ah portable pack sits in the band trailer, with 500w of solar at 240v and is used for running the centrifuge, power tools, outside lighting for get togethers and sometimes electric music. Without the trailer it stays at home, have been thinking of running it in parallel with the bus 480ah pack. If there are adverse effects, would like to know what they are, would hate to lower the life span of the 120ah pack, considering it has been cruising along for 11 years without a problem and same for the bus pack.

Hi NP, if you use longer cables to the aux pack than those from the main pack that powers everything then they will just remain topped up. If the cables are shorter however, the 120 Ah pack will become the supply pack and the 480Ah battery will just be an aux tag on that offers very little to supply load until the 120Ah pack is completely drained. You can try to get the resistance between the load and the battery packs identical and that will help, but the battery pack with the least internal resistance will still be the main supply until virtually exhausted causing the resistance to increase, then the other pack will take over. Eventually the pack with the lowest resistance will have been tortured to the degree that the internal resistance increases till it is the same as the other pack, then they will sort of work together.
It's an exaggerated effect that lead acid batteries suffer, add a new battery to the old battery pack and it will get hammered until it is as stuffed as the older batteries. Lithium batteries have a much lower internal resistance so the level of torture is far higher and can result in that battery being destroyed rather than just damaged. This is why lithium batteries can not be connected in parallel the same way lead acid batteries are, the battery wil the least resistance in the cabling and internal resistance will do all the work, t won't be shared across the whole pack.
There is an article on the UK Smartgauge site that tells the story about what happens when multiple lead acid batteries are connected in parallel, multiply that effect by 100 and you get an idea of what will happen if lithium batteries are connected up the same way.
http://www.smartgauge.co.uk/batt_con.html

T1 Terry
Be aware, even though that site claims the loads are perfectly balanced by method 3 or 4, they aren't and they certainly aren't when using lithium batteries. What the writer failed to bring into the calculations was the battery's internal resistance. This resistance is different for every cell in a battery and adds up across the number of cells, so times 6 for a 12v lead acid battery and x 4 for a 12v lithium battery. Put 6 low resistance cells together and even though the cables are the same length, that low internal resistance battery will be doing all the work until deeply discharged.

Been my concern since they have released the plug and play battery’s
New there had to be a catch some where with them to many cheap retailers bragging how great they are
One stating they can’t be used in parallel and then another saying series yes then no, then they get even more cheaper and now turning up nearly in milk bars (rember them)
So I’m still sitting on the fence watching the

Thanks Terry, thought, it may be something else other than the obvious.

slug wrote: ↑Sat Mar 16, 2019 7:56 pm Been my concern since they have released the plug and play battery’s
New there had to be a catch some where with them to many cheap retailers bragging how great they are
One stating they can’t be used in parallel and then another saying series yes then no, then they get even more cheaper and now turning up nearly in milk bars (rember them)
So I’m still sitting on the fence watching the

Some of the prices offered for 100Ah batteries lately are alarming, I saw one offered for around the $600 mark. They can't be actually building these batteries and including a useful BMS at that price, so the seller couldn't be making a profit unless the batteries are being sold at less than cost to simply get rid of them.
The question then is:
the seller knows there is a problem so wants to get back something for this worthless stock?
or
the manufacturer knows there is problem and is dumping them to at least get something for this worthless stock and the seller isn't smart enough to know better?
or
the battery isn't actually a 100Ah battery but rather an equivalent to a 100Ah lead acid battery, so actually only a 50Ah battery and either the seller is telling porkies or the manufacturer and again, the seller doesn't know any better?

The problem is, the buyer needs to know just what they are getting and the general knowledge level out there is less than zero if gauged by the armchair guros posts on another well known forum that banned me some time back, and of course the knowledgeable folk on Facebook

T1 Terry