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Pedro_The_Swift
1st March 2021, 08:24 AM
I would like to go Lithium in the new caravan, but the same requirements as now, the van needs to be its own master, it must live in total isolation from the tow..ATM I dont EVER think about 12Vcapacity in our old Golf. 500 odd watts and 340 odd Ahrs seems to have worked well for the last 8 years. [smilebigeye]
As this is a Forever Van I want to get it right first time and not just get whatever the van manufacturers can buy on special that week-- [bighmmm]

I keep hearing rumours about full size Dometic fridges running around 10Ahrs( this lead Mrs Pedro to ask why not two 95L Engals? :o:o)
which to be truthful 10 blows my brain a bit.. no wonder most new vans tie up to a wharf each night..

I would imagine the list of power draw starts at the fridge, say 10, add 3 for the TV, 5-6 for the stereo, anyone know the draw from Satellite TV?


As always-
All comments and advice gladly accepted..
especially you Inc..[tonguewink]

W&KO
1st March 2021, 01:01 PM
Iíll have a crack...

Re: new fridge - 10ah/hr constant or only while cycling. Grab 2 x cans off XXXX each time you open the fridge and you will save some power.

I follow a page on Facebook thatís seem pretty good, it more aligned to building your own with separate BMS.

Given your happy with current amount of capacity and solar....looks like you only need to take into account the new fridge usage. Going to lithium isnít any different to selecting AGM. You need storage (to match you usage) , a means to charge (alternator, 240v and solar)

Going to lithium will be influenced by budget....big capital outlay at the front end but once installed it set and forget.......

your current setup as 150-200 usable amps and youíre getting by fine

Re: battery - 1 x 300 lithium or 2 x 200ís

Solar - The good olde internet bashes on that you need to double your storage AH in solar panel watts......depending on roof design on caravan this could be a challenge. Install as much solar as you can fit.

DC-DC, solar controller, a shunt, maybe an inverter are all pretty straight forward.

Enderdrive are doing some nice pre-assembled units, you just need to select battery size, all plug and play, including the 240 Side for the caravan builder. I found Enerdrive product support amd engineers easy to chat to.

It might be worth reaching out to Jason @ Off Road Living, I found these guys very helpful.

Caravan manufacturers should be across it by now......although some research in the bag is handy when chatting to them

Good time to ditch gas as well [emoji6]

Pedro_The_Swift
1st March 2021, 01:13 PM
Need to readup on Lithium charging... the only 240V we use ATM is Di's CPAP,


Have heard good things about Enerdrive,

ditch gas?!?! are you bonkers??? I'd be divorced quick smart! Diane does bang on a lot about cooking with gas,, but not as much as she bangs on about NOT cooking with gas[bigrolf][wink11]

Homestar
1st March 2021, 02:00 PM
What do you cook on if you ditch gas and want to be stand alone? Induction? Always seems such a waste having to over spec the entire system - inverter, batteries, cables, etc to use electric for cooking off grid when gas is so available anywhere and if youíre only running a cooktop a 9kg bottle lasts ages. Want to simmer a stew for a couple of hours - forget it on induction and batteries.

Homestar
1st March 2021, 03:29 PM
To answer your questions from where I see them Pedro.

Fridges - yes, most caravan full sized fridges use a wad load of power when running on 12 volt - they're only designed to run off 12 volt from the tow vehicle and be used when in motion - the rest of the time it's gas or 240 volt. If I was doing something from scratch, I'd use 2 x 90 litre Engels - 1 fridge, 1 freezer - power draw from the pair will be around 3.5 amps with both running and easy to keep up with off batteries and solar with a stand alone system.

I keep my 90 litre Engel in the van off 550 watts of solar and 1 x 100Ah hour lithium, using Victron solar controller and battery monitor - see pic below Lithium battery is from Drivesafe - very happy with it. The solar controller has a lithium setting so that looks after the charge profile. You'll need a battery management system that can keep track of what goes in compared to what comes out as the voltage on a Lithium stays almost the same right until the end, so using a standard voltmeter like you would for AGM won't work. The other think I like about the Victron units is they Bluetooth to your phone so setting them and keeping an eye on things if you want to is very easy although it was a set and forget type of thing for me - once I knew how quickly it charged each day, I never really bothered to check it again.

I've actually just removed all of this from the van and will be fitting it to the motorhome instead as the van will be up for sale at some point and I wouldn't get my money back on this stuff and it's proved brilliant. I will be adding a second lithium battery into my new system and using around the same solar - I've found that even on overcast Victorian days, the battery was full by lunch time even if I'd been running the TV, heater, etc along with the fridge. I will be adding a large inverter to Stan - only to run the coffee machine once a day, but I think 600 odd watts of solar would still take carer of that no dramas.

Other thing I'll add to Stan is a 240 volt charger that has a lithium profile so I can charge it when it's plugged in - we do use caravan parks with it as well, so might as well take advantage of that - I won't be hooking the lithium up the vehicle to charge - that would required yet another device and it really won't need it once the panels are on the roof shortly. I never charged the caravans system from the vehicle either - never needed to with this system.

https://www.aulro.com/afvb/attachments/lithium-batteries/169157d1614576585-recommended-papers-pdfs-websites-charging-lithium-batteries-battery-stuff.jpg

W&KO
1st March 2021, 03:36 PM
Need to readup on Lithium charging... the only 240V we use ATM is Di's CPAP,


Have heard good things about Enerdrive,

ditch gas?!?! are you bonkers??? I'd be divorced quick smart! Diane does bang on a lot about cooking with gas,, but not as much as she bangs on about NOT cooking with gas[bigrolf][wink11]

Charging lithium is not a lot different than how your charging your existing AGM.....all decent brands of 240v chargers and solar regulators have a lithium setting/profile...set and forget.

Yeah ditching gas isnít for everybody especially when youíre towing.....weíre not towing so induction and 12v oven covers all our cooking needs.

What size inverter does a CPAP need.....?

Homestar
1st March 2021, 03:50 PM
So was just looking at freezer draws so I could run a small freezer under the 90 litre engel in Stan and found these - Bushman 190L 12V Caravan Fridge | Free Shipping (https://bushman.com.au/product/dc190l/?attribute_pa_color=black&gclid=CjwKCAiAm-2BBhANEiwAe7eyFH0wi1ZhsS1Y7t0iM-Mzm2nL3gwT-5JiYtiU1oAM7niETpszTKuljxoCEEIQAvD_BwE) & Bushman 285L 12V Caravan Fridge | Free Shipping (https://bushman.com.au/product/dc285l/?attribute_pa_color=black)

Runs a proper 12 volt compressor system so light on the power draw unlike the 3 way units that are mostly for sale - cheaper than 2 x 90 litre Engels too. Now I'm thinking of a revamp of the fridge area for Stan...

Tombie
1st March 2021, 05:03 PM
What do you cook on if you ditch gas and want to be stand alone? Induction? Always seems such a waste having to over spec the entire system - inverter, batteries, cables, etc to use electric for cooking off grid when gas is so available anywhere and if youíre only running a cooktop a 9kg bottle lasts ages. Want to simmer a stew for a couple of hours - forget it on induction and batteries.

Diesel.

Tombie
1st March 2021, 05:05 PM
So was just looking at freezer draws so I could run a small freezer under the 90 litre engel in Stan and found these - Bushman 190L 12V Caravan Fridge | Free Shipping (https://bushman.com.au/product/dc190l/?attribute_pa_color=black&gclid=CjwKCAiAm-2BBhANEiwAe7eyFH0wi1ZhsS1Y7t0iM-Mzm2nL3gwT-5JiYtiU1oAM7niETpszTKuljxoCEEIQAvD_BwE) & Bushman 285L 12V Caravan Fridge | Free Shipping (https://bushman.com.au/product/dc285l/?attribute_pa_color=black)

Runs a proper 12 volt compressor system so light on the power draw unlike the 3 way units that are mostly for sale - cheaper than 2 x 90 litre Engels too. Now I'm thinking of a revamp of the fridge area for Stan...

Iím a fan of the draw fridges.
You can install multiple units, have a decent capacity if needed and only run those you do when you donít need the others.

3 will give 120l capacity - 80l fridge, 40l freezer or any combo.

Homestar
1st March 2021, 08:19 PM
Diesel.

Ah yes - True I suppose if youíre pockets are bottomless and weight is no issue. Havenít seen many of these and the cost is eye watering from what Iíve seen but probably no more or even cheaper than stuffing in as many batteries as you would need to run induction.

Pedro_The_Swift
1st March 2021, 09:37 PM
Thanks Gav,, That Bushman could turn out to be the ducks! [bigrolf]
max 4.5 and av 3A??? Unbelievable!

incisor
2nd March 2021, 09:28 AM
Thanks Gav,, That Bushman could turn out to be the ducks! [bigrolf]
max 4.5 and av 3A??? Unbelievable!

they are nice units....

Pedro_The_Swift
2nd March 2021, 11:58 AM
Found this--
How to Find Happiness With LiFePO4 (Lithium-Ion) Batteries - Solacity Inc. (https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/)

might have to aircon the battery box... :o

Homestar
3rd March 2021, 10:29 AM
Not sure how you could keep them below 30 or even 45 degrees over here - even down south here, much less up your way.

Mine has lived inside the van and now resides under the front seat in Stan - that seems to be a step backwards as it will potentially get much hotter in there so may have to rethink this before next Summer, which is quite possible as at some point I want to add a decent inverter and that won't fit anywhere near where the battery is at the moment.

StormCamper
6th April 2021, 04:09 AM
What do you cook on if you ditch gas and want to be stand alone? Induction? Always seems such a waste having to over spec the entire system - inverter, batteries, cables, etc to use electric for cooking off grid when gas is so available anywhere and if youíre only running a cooktop a 9kg bottle lasts ages. Want to simmer a stew for a couple of hours - forget it on induction and batteries.

I spent a bomb on my lifepo4 setup and i would never really cook on induction unless solar was very strong, which it almost never is plus another problem of induction is you really want to go electric water heating or else why bother? you still have the gas bottle, but electric shower heating is just the final blow power consumption wise. simmering is not that great on induction cookers that simply vary the duty cycle of a fixed input power.

Pedro_The_Swift
6th April 2021, 08:11 AM
OK,, from what I have read so far,
Lithium runs quite nicely not at 100% charge, in fact its better on the battery not to reach 100%,
This might be a problem for vans that "sit" outside, waiting for the next trip.

drivesafe
6th April 2021, 09:36 AM
Some of my lithium batteries are now close to 9 years old and I have always kept them at a 100% charged state between uses, and this is regardless off whether they are being cycled on a daily or left for years at a time.

To date, they are all still supplying full discharge capacities.

I deliberately left a couple of them, originally intended to be for two years, but was close to 4 years, when I carried out a discharge cycle on both, and found they had lost just 4% of their capacity, which was regained in the next charge/discharge cycle.

So far, I have only managed to damage ( intentionally ) two lithium batteries and this took quite a few 400% discharge cycles before each battery dropped a cell.

As mentioned, this type of testing was being carried out for another company as they wanted to know what these batteries could tolerate as very little spec info was supplied back then.

I must say, I was very impressed as most lithium batteries are now limited to between 75% to 150% maximum continuous discharge currents.

Blknight.aus
6th April 2021, 05:33 PM
Start with reading the manual that comes with the battery..... it will let you know what you need to do, then just find a charger that does what the battery wants.....

Keeping them at temp is relatively easy if you have the prior planning, nest them in a "dounut" water tank with insulation. keep your water tank reasonably full.

d2dave
10th June 2021, 11:22 PM
Start with reading the manual that comes with the battery..... it will let you know what you need to do, then just find a charger that does what the battery wants.....

Keeping them at temp is relatively easy if you have the prior planning, nest them in a "dounut" water tank with insulation. keep your water tank reasonably full.

Dave, can you elaborate a bit more on this dounut water tank.

PhilipA
11th June 2021, 08:54 AM
I have just fitted a 100AH "cheapie" Lifepo4 to my newly acquired 2003 Coromal SEKA Pioneer 505 XL. It is a Voltax which I have seen a review of as actually being a100AH battery rather than the many 70AHs being sold as 100AH.

It should supply for ever as it is only running the caravan lights and pump most of which I have changed to LED.

I have removed the X7 charger and fitted a 10amp ac/dc charger ( Big Wei) which is for lithium batteries only and charges at 14.6V which is the specified charge rate for the Battery..It is just a Chinese charger but the one for my wife's buggy battery has performed well with the addition of some Jaycar alloy heat sink and conductive paste. The 10 amp one has a fan even!

In addition I have fitted a Renolgy 20/20Amp DC/DC charger which is fed by an 8 SWL feed(and earth) from the car via a 2pin 50Amp trailer plug (Supercheap) . I will not use an Anderson Plug in this application as I have seen them pulled out by track centre vegetation.

The circuit is controlled via a switch and relay connected to the accessory circuit to the original rear plug in the D2, so I can charge from solar from the second battery in the car if warranted by just turning the ignition switch to accessory. The feed is the main 4SWL feed from the second battery to the back of the car. I need plenty of amps as I have an Anderson Plug to run my 50amp compressor. The Anderson plug is located inside along with a Hella plug ( and 2USB )on top of the RH rear corner plastic trim above the air exit vent.

The battery only has a max discharge rate of 50amps or 0.5c so is in Drivesafe's opinion not worth having but my potential draw is much less than that , although I cannot use a big inverter to run say a coffee machine or toaster.

In any case even at 1c it would need another battery as an ALDI coffee machine uses 1500watts so over 1C and would need a 2000watt inverter.

I am soon to buy and fit a fridge switch .

I am still deciding whether to run the fridge from the van battery with a fridge switch in circuit, but the location of the wires is a bit of a mystery as yet and it is early days. Seeing it is winter I will leave that until later

Next job is to sort the hoses on the two 80Lwater tanks which are joined in a very strange manner and do not have drains!

Regards PhilipA

drivesafe
11th June 2021, 11:10 AM
I am still deciding whether to run the fridge from the van battery with a fridge switch in circuit, but the location of the wires is a bit of a mystery as yet and it is early days. Seeing it is winter I will leave that until later
Hi Phillip, is this a 3 way fridge?


If so, even with Lithium batteries, it would still be safer to run it of your D4, direct, rather than off the house battery.


Even the small 3 way fridges can flatten a lithium battery in a short period of time, and then you have to find some way of recharging your lithium battery.

Plus your DC/DC will struggle to charge the battery while running the fridge off the battery at the same time. You will need to do some very LONG drives to get the battery recharged.


The Fridge Switch is always a great addition but if you can pick up a feed from the FRIDGE output on your D4, you will have the perfect fridge operating system and you will not need the Fridge Switch.

PhilipA
11th June 2021, 03:55 PM
The Fridge Switch is always a great addition but if you can pick up a feed from the FRIDGE output on your D4

Oh to be wealthy enough to own a D4 when one is a humble D2 man.

Currently (get it?) the fridge is run from the power wire in the 7 pin plug which is AFAIK from the starting battery and unswitched .

I could switch it to the switched accessory feed to the DC/DC charger I guess which would only involve tapping the input to the DC/DC charger in the boot of the van.
Regards PhilipA

Blknight.aus
11th June 2021, 09:05 PM
Dave, can you elaborate a bit more on this dounut water tank.

its just a tank with a hole in the middle you can put the battery in.

picture a box in a box the battery goes in the smaller box and the water goes between the bigger box and the smaller box.