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Yes, I have seen this video. Even though the guy (Stephan?) did get the DCS batteries for free his review seems fairly unbiased. Impressed with the DCS BMS. Certainly seems more substantial than some of the eBay lithiums. Also bluetooth monitoring of individual cells seems nice.Quote:
Originally Posted by W&KO
Hey Brian, i mean Briar, its Stefan, not Stephan[emoji1787][emoji1787][emoji1787].Quote:
Originally Posted by Briar
Sorry, couldn't help myself[emoji1]
No probs Bern!Quote:
Originally Posted by Vern
I'm 3 years into my LifePo4 Lithium batteries in the caravan journey. This is what works for me, rightly or wrongly...
D4 with Traxide & 2 dual batteries, one behind the headlight & the other in the box on the driver's side. Anderson plug on the towbar connecting the van to the Traxide system through a 50A DC2DC with a separate remote control.
Caravan with 2 CALB180AH battery packs connected in parallel so 360AH total. BMS is external & something I built myself. Also, Victron solar controller, 600W of panels & a Victron Multiplus 3KVA AC switch/inverter/120A DC charger. Cheapie generator off evil bay. RVD protection on the 240VAC mains.
Lithiums can be charged via solar or by the Multiplus if 240 is available. Batteries charge from 240VAC in 3-4 hours depending on Bluetooth enabled settings in the Multiplus. The generator can also supply enough power to charge in 2-4 hours too. I sometimes use the DC2DC to charge along with the solar while travelling & running the aircon to keep the temperature in the van at 28deg. Having endured 2 weeks at a site north of Cloncurry where temps are above 40 every day, keeping the van cool is important.
If the DC2DC + solar is not keeping up then I will run the generator located on the back bumper of the van while travelling to keep the van cool & charge the batteries.
So, when I stop for the night, my van does not take much to cool to 24 or so & the batteries are full. Like Tuesday night in a gravel pit outside Kynuna at stupid temperature, I set the Multiplus to only accept 3.2A from the generator. This dials the generator noise down to acceptable in the van so as to run it all night. My 3000W generator effectively becomes a 1000W generator.
I am hearing people saying but you can't run AC on 3.2A. This is true unless the batteries are assisting which is what happens in my system. Through the night, when the AC ramps up, the batteries supply any current needed above 3.2A through the Multiplus Assist Feature. When the AC ramps down & doesn't need 3.2A, the Multiplus charges the batteries.
I'm not in it for the calculations as to which technology (AGM or Lithium) is more cost effective in the long term, I don't care. I need power while mobile & I need to replace that power quickly when necessary in order for my system to function like it does. I can't fault the charging characteristics of my Lithiums, they take everything you can throw at them until fully charged. But, the battery management system needs to be external to the batteries, not like the drop in varieties where the BMS is contained within the battery & you have no control over the charge/discharge settings.
I have recently fitted a Victron SmartShunt to the Traxide on the D4. This is producing some interesting results when the D4 is stopped. The vehicle is power hungry for a while even when stopped it seems.
Thanks for the detailed replay.Quote:
Originally Posted by Milton477
Re: external BMS, if/when i need to upgrade I will go down the external BMS with separate battery pack.
Cost wasn’t a factor when I switched as their was a bunch of other requirements that needed to be met amd lithium was the solution.
Re: calculations, I’ve never added project usage and Amps......have always just installed what I could afford at the time with my fall back being the charger attached to the motor and/or add to the system later.
Hi again Briar, while the DCS batteries would be an overkill in caravan use, because their higher price is based on their ability to take and give high currents, required for starting motors and then being able to be recharged quickly after starting the motor. Just like lead acid batteries are designed to do.Quote:
Originally Posted by Briar
While it would not be that advantageous to use a dedicated lead acid cranking battery as a house battery, there is actually a potential to use a lithium cranking battery as a house battery and SAVE MONEY.
It all depends on how you intend to use your house battery, or number of house batteries, depending on your specific needs.
If you are looking at running an A/C then you will need a number of lithium house batteries but they do not need to be cranking type, because you are more in need of large capacity, so you can run the A/C with high current needs as well as the large capacity to operate for long periods of time.
Standard, good quality lithiums will easily meet this need as the high current demand will be spread over a number of batteries, thus reducing the current demand each battery.
But if the for the majority of your use, you are only powering very lower current devices like compressor fridges, camp lighting and a small inverter for charging phone/camera/computer batteries, and your high current demand is just for short periods, like running a toaster, or microwave or even an induction stove, then because of their ability to provide very high currents from a single battery, on demand, a single DCS may very well meet your needs.
So while they are expensive, again, because of their ability to provide very high currents, you may only need a single battery, thus saving you money by not having to buy ( and carry ) a number of batteries.
It always comes back to your specific needs as to what you will actually need.
Hi TimQuote:
Originally Posted by drivesafe
Thanks for that. I was focusing on the DCS batteries BMS as being critically important. I'm wasn't really considering that the extra cost of the DCS was purely because of the current draw that they allow. I am running a large compressor fridge and have a small 800 watt inverter as well as all the normal 12 volt stuff. Certainly no intention of any high draw needs from the battery such as microwave, toaster or A/C. Based on what you have said lower cost Lithium such as the iTechWorld's might well be sufficient??
Certainly nicer to pay $800 each rather that $1200 that DCS would entail.
We currently have 250 Ah of Full River AGM but are 5 years old and pulled them out to get load tested. They are at about 80%, so only good for about 200Ah. Pulling them down to 50% I effectively only get 100Ah of usable power. One 100Ah Lithium would be close in current comparison, but would not be enough. Three months back I was at Adels Grove/ Lawn Hill. Over 30-35 degrees each day and pretty cloudy. Even with 405 watts of solar on van roof and 150 watt blanket that I moved around I still ended up with only 45% left in batteries after just 2 days. Was intending to stay at Adels for 3 days and then some other free camping so could have really run out of power. I will probably still go for 2 x 100Ah.
What is your opinion in the iTech ones? I realise that just because every second person who has them says they work great, those comments are often after after less than a year of use.
Thanks for your thoughts.
Hi Briar, you might want to do some checking about Itech. They have a very bad reputation of supplying anything but correct specs for many of their products.
While they market a 120Ah Lithium battery, it is, according to them, only good for 80% of that?????????
First off, I have had absolutely no hands on experience with Solarking batteries, but I have been trying to check them out for some time, after looking at their specs.
They quote 2000 cycles down to 0% capacity. In other words, their 100Ah battery will supply 100Ah for use, and that’s pretty reasonable.
Their specs are slightly better than average, but taking into account their low price, these seem like a good buy for the usage you are intending.
BUT, you need to do your own investigation, to make sure they are as good as they say.
Quote:
Originally Posted by drivesafe
Hi Tim. Have just visited my van and pulled out the two batteries.
The one that came with the new van in late 2015 - Black Case called Positive Batteries Deep Cycle DC100-12S. Was down to 7V and is currently on my wee MXS 5.0 12V 5A 7/8 stage charger for a week to see if it can be rescued - not holding my breath.
To explain the 7V, my solar panel ended up upside down (slightly possible in recent storms, but??) and there was a week between all good and when the van went in for its annual service (at which time I discovered the "disturbed" solar panels, and was subsequently told by the shop that the batteries were shot).
Second one - INTERESTING - Red Cased Ultimate Extreme UL100VO BCI Group 27 - bought from Batteries Plus sometime in 2016/7 but can't find the receipt - now found to have vertical crack lines in the outer case down both of the long sides corresponding to the edges of individual cells. Given that this battery has spent its whole life encased in an ARK Power Pack case, the cracks are a concern - no acid escaping as yet. I've left it on the charger for 3 days and currently up from 7V to 12.6V, but waiting to see if it will hold charge - load tester has indicated it is on the weak side.
At the risk of going even further off topic, I have 2 new (August) Bosch SM 90D26R batteries under the bonnet of my RRC which don't seem to charge above 12.6V once settled - is this normal? They will show around 12.8V just after coming off full charge.
My Nanocom Evo shows around 14V +/- 0.2V as I drive along, so a significant difference.
Hi Gavin and as the second battery actually sounds like it might have been overcharged, to cause the cracking, just maybe, this is the reason for the potential failure of the other battery.
Also a bit strange for solar panels being upside down to be the cause of any problems. specially over such a short time period.
Do you know what the operating voltage settings are for your solar regulator?
As for the Bosch batteries. At a settled voltage of 12.6v. That is actually pretty good and indicates an SoC of around 95%.