HI again, looking at upgrading the battery system from a 220 A/Hr Lithium (2 x 110) to a 520 A/Hr Lithium (2 x 260), what amount of solar panels woud you think I require to activly charge them ?
As much as you can reasonably fit on the roof because flat panels do not produce anywhere near their maximum. The output is also affected by your geographical location (sun angle and weather), whether you stay in one place for extended periods and the type of areas that you camp such as shaded areas. That is why some people such as myself have a DC/DC charger and also carry portable panels with an extension lead.
Are you currently running out of power and if so in how many days? Do you have any idea of how much power you are using each day?
What brand of 260Ah batteries are you looking at and what brand are you current batteries if you don't mind me asking?
260Ah is a nice lot of lithium, 520Ah is even nicer
Hi and thanks for the feed back, currently I am away and not near my van, so I cannot tell you what brand they are, but the dealer put them in , so I would not expect them to be the expensive type... I am looking Giant batteries as they do the 260 AH.. At present we have 300 amps of solar on the roof, so i know that will require up grading.. The DC/DC Charger sounds good to me, as do the portable panels (maybe the flexible type for less weight..)
Tim, the GIANT batteries have a 5yr warranty and also they say can do 5000 cycles.. I would love to go Enerdrive, but the budget does allow... The Giants are $1560 each.
I have not had any issues with Aussie Batteries and their Giant brand. I have one of their AGMs at home that I have had for a good few years and a capacity test earlier this month showed it is still at 100%.
The quality of the cells in the Giant battery will be equal to the ones in an Enerdrive battery or any of the other expensive batteries. They are just similar cells in a different case. The BMS is a Daly BMS which is also a quality 200A BMS with Bluetooth capabilities.
They have a maximum continuous discharge current of 200A so two in parallel will run a decent size inverter if need be.
Personally I dont think you will go wrong with these and if I were thinking of buying lithium batteries then the Giant brand would be at the top of my list. Fortunately I havent needed to as I buy my cells from China and build my own.
Tim
-- Edited by TimTim on Monday 25th of July 2022 07:20:51 AM
As said, are you running out of power and how many days can you go with inclement weather. Having a portable panel to face square onto the sun and reach the sun with long cable maybe a better option when needed.
We can easily go 4 days with only 104AH, technically 7 days as we are only running a small fridge.
I have 120 watts custom built portable which is outputting 9 to 11 amps via Victron MPPT near the batteries. All with 6awg & 4awg cable
When panels are flat on the roof about twice the wattage is what you need, but basically as much as you can.
But be very careful to avoid shadows. A small shadow can nobble the whole system. So you will be better off with a bit less on the roof if you have roof furniture (satellite dish etc) which may cast shadows.
Watch your payload, solar panels are heavy.
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50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
No not running out of power, as have not used the van that much to find out.. But just want to upgrade now, so when we do finally hit the road for long periods, i wont have any ssues (hopefully that is) .. I run a 2000W Enerdrive Inverter at present, but again have not used it, since having it installed.. My plan is to upgrade the battery size in the van and use the 2 x 110 Lithiums in the Cruiser (if they fit that is).. I know absolutly nothing about electrics, so all your advice as been excellent, thank you.
520Ah of lithium is about 7kWh which is more than a half of the energy I use to use in a house. For a caravan it is enough to run air-conditioning and microwaves etc.
Understand that buying more battery will not give you more energy eg. if it rains 50mm each day it matters not whether you catch that in a 10L bucket or a 100L tank you still only get 50mm of rain.
OK: let's assume you use 5kWh of those batteries every or most days (otherwise why pay for them?) - to replace 5kWh with, say, 800W of panel:
800W panels will, in reality, put out about 700W in full (need a hat) sun providing they are freestanding, at the correct angle with no shade or cloud.
So in excess of 7h of full sun is needed every day and you'll need a MPPT regulator capable of handling at least 50A plus all the associated heavy duty cables and inverters.
Are you *really* sure you need this much power? I use between 600W and 1200W each day and only that much because I'm a bit lazy in the way I have my system organised and usually have power to waste.
Your current 220Ah gives you about 3kWh of energy which you are charging with 300W of flat solar panel which, in reality, is probably generating 200W if you are lucky. If you are using 2kWh per day those panels will take around 10h of full sun to recharge the battery - which isn't going to happen.
I strongly suggest you do not, at this time, upgrade the batteries but rather upgrade your panels by buying another, say, 300W of free standing panels and adding those to your system.
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"I beseech you in the bowels of Christ think it possible you may be mistaken"
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Although many people do, I would not recommend putting lithium batteries under the bonnet. Cold and heat are not friendly to them.
About three years ago camping at Charnley River Station my neighbour showed me his Stuffed Lithium Battery that was mounted under the bonnet.
The supplier salesman (well known company) told him it was OK to put it there. The Auto Electrician they reccomended said he would not fit it in there as it would fail due to heat.
The suppliers (Salesman) said "again" it was OK under the bonnet get another Auto Electrican. The next electrician said it was not advisable.
The guy told me he was short of time as he needed to get going on his trip (from Perth around Australia) So he did it himself.
Perth to Charnley River along the Gibb River Road and he had no battery, he was also lamenting he had probably voided warranty by doing it himself.
In all probability the cells in the battery may of been ok but his BMS may have shut off if there was a temperature sensor inside the battery or the BMS may have been cooked. I have no idea what temperatures are achieved under a bonnet but obviously dependent on where they are located it can get very hot. Most BMSs are designed to shut down to prevent charging at below 0C or above 55C. The cells themselves may be able to withstand higher temperatures than that provided they are not being charged.
The other issue is that once some of the BMSs shut down they either need to have a reset button or a jumpstart to activate them again. Being under the bonnet with an alternate power supply jumpstarting didnt work.
It would have been an interesting project to open up the battery, test the cells and install a new BMS if the warranty claim was rejected.
Tim, the GIANT batteries have a 5yr warranty and also they say can do 5000 cycles.. I would love to go Enerdrive, but the budget does allow... The Giants are $1560 each.
Hi again KB,
Smiling as I do not get too excited about how many cycles they are capable of. The reason being, say we take a conservative figure of 2000 cycles for the batteries. Even if we were to run the batteries down through a 100% cycle for 200 times a year then they would last 10 years. Even then at the end of that period they would still supposedly have 80% capacity so 416Ah. Admittedly, they are supposed to degrade at a faster rate down from 80% but even after say 10 years most of us will either be long gone, given up travelling or the technology would have changed by then .
If you read back through the thread and are able to provide us with some more information, just like Mike has suggested you may not need to spend $3120 on batteries as it may be a case of a few hundred $ a DC/DC charger if you don?t have one, some portable panels and a MPPT controller.
It may still be advantageous to put additional panels on your roof but consideration has to be given to the the additional load, existing wiring size and your existing solar controller.
HI again, looking at upgrading the battery system from a 220 A/Hr Lithium (2 x 110) to a 520 A/Hr Lithium (2 x 260), what amount of solar panels woud you think I require to activly charge them ?
Hi Branchie,
I assume you currently have 2 x 110AH batteries connected in parallel. You need to confirm in the manufacturers specs literature whether you can connect 4 x 110AH batteries in parallel and acquire another two same or similar batteries capable of connecting all in parallel giving you a total of 440AH. If all batteries are compatible then the BMS will work together. More than enough for future requirements and cheapest way to move forward.
Next you need a good quality brand MMPT solar charger. (40-80A)..not a no brand imitation Chinese mmpt one which is actually a PWM. Then depending upon your power usage requirements suitable solar panels, perhaps starting with 4 x 200/250W fixed panels if your situation allows, and add more if required with portable panels. A base of 800/1000W of panels (400/500 in reality) will give you plenty to charge the batteries even in inclement weather, especially if you have some backup in portable panels. No need for dc/dc charging or gennie. Solar will be sufficient. Then have a decent inverter (and capacity) to run 240V appliances. With that setup you will never look back. No need to go over the top with cost, plenty of good quality panels, controllers, batteries and inverters out there.
Do a search on the Forum regarding Lithium Batteries, plenty of info here on your topic.
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Cheers, Richard (Dick0)
"Home is where the Den is parked, Designer Orchid Special towed by Jeep Grand Cherokee Limited"
"4x250W solar panels, Epever 80A charger and 3x135Ah Voltax Prismatic LiFePO4 Batteries".
Seems you need more charging ? As in more solar ? I find fitting near double what you need in theory as you need some envelope for clouds etc batteries should be fully charged by mid day !
-- Edited by Aus-Kiwi on Wednesday 27th of July 2022 08:49:27 AM
I have not had any issues coupling two LifePO4 together but with one larger battery the less components then the less chance of things going wrong. The advantage is with paralleling a number of batteries is if something does happen with one BMS it is easy to disconnect that battery and still have some power.
I have not had any issues coupling two LifePO4 together but with one larger battery the less components then the less chance of things going wrong. The advantage is with paralleling a number of batteries is if something does happen with one BMS it is easy to disconnect that battery and still have some power.
Exactly!
That is the advantage of having multiple batteries.
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Cheers, Richard (Dick0)
"Home is where the Den is parked, Designer Orchid Special towed by Jeep Grand Cherokee Limited"
"4x250W solar panels, Epever 80A charger and 3x135Ah Voltax Prismatic LiFePO4 Batteries".
Ellie Mike,
3 years in high tech days is a long time. I believe that some lithium batteries are on the market now that can take "engine temperatures". I know it took years for lead acid batteries to be built to serve in the same conditions. I reckon a 4.2L TD Nissan Patrol should be the test vehicle for auxillary batteries!
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Warren
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If you don't get it done today, there's always tomorrow!
I find solar and the odd engine run bridged gives me enough ? If not the batteries may not be holding charge ? Lithiums should get what you want . Not sure why you need so much more battery ? Considering lithium hold deeper cycle and charge faster !! More than one battery is a size or storage thing for me .b400 watt solar / 300Ah AGM. just fitted 250 AH lithium working fine . Have the option to fit two more in parallel..
-- Edited by Aus-Kiwi on Sunday 7th of August 2022 09:10:33 PM
I run lithiun in my van and want a robust system. I ended up thinking.....
a. 3x solar panel watts to lithium battery ah's.... so for a 200ah lithium I go 600 watts. In addition I run a 40amp Dc2dc.... b. For extended rainey day insurance.... I carry a 10kg 800w small gennie ($350).... just big enough to run my 30amp 240v charger. Better insurance then a portable panel. c. Because I spend a lot of time camping in the south May to October.... I run 800w of panels now on the roof....as they are less then 50% efficient in winter down south.... 200ah of battery is fine... as battery use is mostly only at night d. the 40amp dc2dc is mostly for late afternoon charging...... so say we stop at 2pm.... microwave some stuff.... make a coffee.... then maybe do another 100km before camp..... sun is low in the sky from 3pm on in winter down south.... so dc2dc helps get batteries back to 100% before camp.
Generally.... we normally use about 100ah max out of our battery from.... say 4pm to 10am ... with solar doing 90% the work between 10am to 4pm April to Ocober down south....
Also... I am in the 4th year of running a lithium under the bonnet in my 200 series.... all going well... but... I did install an appropiately rated one (80 degrees).
-- Edited by Noelpolar on Friday 12th of August 2022 09:14:28 PM
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