Swapping to lithium

[Ranga]

My AGM in the slide-on has expired (8+ years ain't a bad run), so yet again I'm considering going lithium. My set up is as follows:

vehicle has an AGM auxiliary being charged from the alternator (with an isolator)
slide-on has (had!) an AGM, 150W solar panel and Morningstar MPPT solar regulator
[heavy duty connection using Anderson plugs between the vehicle AGM and the slide-on AGM

Getting another AGM is a straight swap, and if I can get 8 years out of another one I might just do that. I'm also considering adding a large inverter to run an electric induction hotplate. Before I stick with AGM, I thought I should get some advice on what components I would need (include brand/model/supplier) to swap to lithium to make an informed choice. Price is obviously a factor, weight and physical size not so much.

Anyone out there care to have make a suggestion?

[philandmickey]

Hi
I have a very similar set up to you.
But I have Ctek DCDC charger that has a solar input. and a 300w solar panel on the roof.
I had 2 x 100amp agms in the camper and swapped them for an Itech I120X.
This gives me the same capapcity (as it can use 80% capacity).
But the big advantage for me was the AGM's weighed 80kg and the lithium 13kg.
It's been fitted about a year now and so far so good.

Cheers
Phil

[W&KO]

If you’re considering induction cooktop the more storage you have the better. To be comfortable you would need at least two AGM’s or switch to a lithium. Keep in mind you need enough up you’re sleeve to run the fridge overnight and maybe some capacity in the morning.

For 2A when the sun rises we regularly see remaining percentage dipping into the 70’s. Lowest to date is 68%. This is on a 200amp/hr battery. So up to 64amp/hrs.

Brands...there is gear to suit all budgets, from super cheap to super expensive.

There is a guy on FB Van Life page testing a few of the cheaper brands, sorting the duds from the good. He is doing capacity testing and these are performing around or above stated amp/hrs.

LiFePo4 Lithium Batteries (https://www.lanplus.com.au/lifepo4-lithium-batteries)

My install is in the upper end pricing with comments

Enerdrive
DC-DC 40+ (check recommended charge rate for battery, most have solar input check if it preferences a charge source, I have an Anderson plug connected to the solar input for a blanket if required, these DC-DC’s seem popular even on budget builds)
2000w inverter (check max. Current draw from battery, we run our induction on 1800w pulling 170amps)
200amp/hr Battery
Low voltage cut out (I wouldn’t run my lithium to 0%)
Remote display (handy)

Victron 100/30 solar regulator. (I run this so battery can take charge from solar and alternator while driving).

2 x 120w semi flex solar. (Not 100% sold on semi flex)

[PWat]

I’ve recently installed a system in my slide-on camper. It hasn’t left the driveway yet but seems to be working in test mode! I calculated I needed 80AHrs usable capacity in order to run my fridge and a few lights for 3 consecutive rainy days.

I bought a 100AHr Enerdrive Lithium:
- Lithium because of space (1 battery vs 2), weight and lifetime;
- Enerdrive due to battery type (prismatic) and brand name. (We were also thrown some Covid-cash from the government when I was deciding what to buy!)
- The more expensive batteries also have a Bluetooth interface so you can check the charge state and current charge rate/consumption. (AGM batteries and cheaper need an external charge monitor.)

I chose the Redarc 25Amp charger rather that the Enerdrive 40Amp:
- It will charge simultaneously from the car and solar. (The Enerdrive and most other units just switch.)
- It’s physically smaller and lighter;
- 25Amps matches my solar panels;
- Downside is that it’s a bit more expensive;
- One advantage of Enerdrive is that you can drive it from household solar panels (which run at a higher voltage). You can get second-hand panels for almost nothing but they are very heavy.


Something to check: your existing charger may have a Lithium setting.

Hope this helps....

[W&KO]

I’ve recently installed a system in my slide-on camper. It hasn’t left the driveway yet but seems to be working in test mode! I calculated I needed 80AHrs usable capacity in order to run my fridge and a few lights for 3 consecutive rainy days.

I bought a 100AHr Enerdrive Lithium:
- Lithium because of space (1 battery vs 2), weight and lifetime;
- Enerdrive due to battery type (prismatic) and brand name. (We were also thrown some Covid-cash from the government when I was deciding what to buy!)
- The more expensive batteries also have a Bluetooth interface so you can check the charge state and current charge rate/consumption. (AGM batteries and cheaper need an external charge monitor.)

I chose the Redarc 25Amp charger rather that the Enerdrive 40Amp:
- It will charge simultaneously from the car and solar. (The Enerdrive and most other units just switch.)
- It’s physically smaller and lighter;
- 25Amps matches my solar panels;
- Downside is that it’s a bit more expensive;
- One advantage of Enerdrive is that you can drive it from household solar panels (which run at a higher voltage). You can get second-hand panels for almost nothing but they are very heavy.


Something to check: your existing charger may have a Lithium setting.

Hope this helps....

Who much solar are you running?

I notice the recommended charge rate of the 100amp/hr is 33amp with a max. of 50amps for 30min.

Maybe something to consider

[PWat]

Who much solar are you running?

I notice the recommended charge rate of the 100amp/hr is 33amp with a max. of 50amps for 30min.

Maybe something to consider

2 x 150w --> 25A

I only installed them a couple of weeks ago and the battery was charging at up to 22 amps which I was pretty happy with given it was mid-afternoon sun and the panels were horizontal.

I bought these - cost effective and not as heavy as some: 12V 150W Monocrystalline Solar Panel | Jaycar Electronics (https://www.jaycar.com.au/12v-150w-monocrystalline-solar-panel/p/ZM9059)

[W&KO]

2 x 150w --> 25A

I only installed them a couple of weeks ago and the battery was charging at up to 22 amps which I was pretty happy with given it was mid-afternoon sun and the panels were horizontal.

I bought these - cost effective and not as heavy as some: 12V 150W Monocrystalline Solar Panel | Jaycar Electronics (https://www.jaycar.com.au/12v-150w-monocrystalline-solar-panel/p/ZM9059)

Thanks...

I was crunching the number on recommended charge rate to max charge rate. More so for my knowledge against selecting items.

Cheers

[drivesafe]

My AGM in the slide-on has expired (8+ years ain't a bad run), so yet again I'm considering going lithium. My set up is as follows:

vehicle has an AGM auxiliary being charged from the alternator (with an isolator)
slide-on has (had!) an AGM, 150W solar panel and Morningstar MPPT solar regulator
[heavy duty connection using Anderson plugs between the vehicle AGM and the slide-on AGM

Getting another AGM is a straight swap, and if I can get 8 years out of another one I might just do that. I'm also considering adding a large inverter to run an electric induction hotplate. Before I stick with AGM, I thought I should get some advice on what components I would need (include brand/model/supplier) to swap to lithium to make an informed choice. Price is obviously a factor, weight and physical size not so much.

Anyone out there care to have make a suggestion?
Hi Ranga, what size AGM are you using right now?

Besides the obvious, is there any special reason for wanting to run an induction hotplate?

[DeanoH]

" Oils ain't oils Sol", or in this case there's lithium batterys and there's lithium batterys. A quick look at eBay will show that a typical 100 ah will set you back somewhere between $350 and $1200. It's a real lithium battery swamp out there and it's full of crocodiles [bawl].

I managed to wade through this swamp last year when I upgraded the Oka house battery from AGM to LiFePO4. Selecting a good lithium battery over a not so good one can be difficult but in the end the initial selection factor I used was weight, not very technical but it became clear (to me) that the better batterys weighed in around 12 Kg and had a warranty of between 3 and 5 years (from a reputable dealer) and the 'not so good' batterys weighed in substantially less than this, some as little as 6 Kg with a warranty of 12 months or so from lesser known vendors.

It may be that some manufacturers have come up with a brilliant battery design that needs only half the mass of active ingredient as other lithium batterys and gladly pass this substantial cost saving on to the consumer, but on the other hand it's possible they're just cheap crap. [bigwhistle] Seriously though, you can do a lot worse than using battery mass as a starting point when selecting a new lithium battery.

A couple of other points to ponder. A typical induction cook top is rated at 2000 watts or around 160 amps at 12 volts of battery current into a suitable inverter assuming no losses so best case at full power. Unfortunately your typical lithium 100 ah battery cannot supply this current so you'd need at least two or 200 ah worth. If you plan on using the same batterys to power an electric winch, forget it as a typical electric winch (4WD Supastore 12000 lb) draws 430 amps at full load. Don't forget your starter motor here as it can draw in excess of 400 amps also depending on the vehicle.

A lithium compatible DC-DC converter is a good idea for lithium battery charging as it a/. provides isolation of an auxiliary (lithium) battery from the vehicle battery, b/. provides optimal charging and c/. limits lithium battery charge current which can be very important in preventing alternator/wiring failure.

The point I'm trying to make here is that upgrading to lithium from AGM may not be as simple as just plugging in a LiFePO4 100 ah replacement battery.

In my case I retained a lead acid vehicle/start battery and connected this via a DC-DC converter to the lithium house battery (2X100ah LiFePO4). The solar is fed by a separate solar reg with its own LiFePO4 charging profile.


Deano :)

[drivesafe]

Hi folks and this is a big, BIG warning to those looking at buying lithium batteries.

You need to make yourselves aware of at least the basic lithium battery specifications to look for, before laying out hard earned cash for these products.

Nearly 10 years ago, I was LUCKY to be asked to test a couple of brands of lithium batteries for a company I do a lot of business with.

At the time, I made it quite clear that I knew next to nothing about Lithium batteries or how to go about testing them.

They made it a point of letting me know that they were only too happy to let me learn about lithium batteries on the run, as it was a learning curve for them as well, because they wanted to source a decent brand to supply their customers with.

To this end, and while I do not rate myself as an expert of any form when it comes to lithium batteries, but I have gained enough knowledge about them to know when a lithium battery is of some quality and when they are nothing but cheap junk.

Back to the thread and while it has been some time since I last looked at what lithium batteries are available, so after reading Deano’s post, I decided it was time once again to see what was out there.

I could not believe how pathetic some of the “well known” brands were.

Two in particular stuck out, and this is where having a basic idea of lithium battery spics comes into play.

Both of these brands were being touted as being 100Ah batteries, but they were being marketed as only being able to provide 2,000 cycle down to 20%.

One of the advantages of using Lithium batteries is that they are “supposed to” be abled to cycled down to 0%.

So for a starter, these well known brands of 100Ah lithium batteries were actually only 80Ah batteries.

While you can take this as a plug for my brand of lithium batteries, but the intention is to demonstrate the differences, as mine come with specs stating they can be cycled down to 0% 3,000 times.

This means the DEARER well known batteries have a total throughput of 160,000 amperes compared to my battery’s 300,000.

The DEARER batteries had a maximum continuous discharge rate of 100 amps but then this was only guaranteed for 30 minutes, while mine can be full discharged at 100 amps to 0% capacity.

Again, you need to be able to know what the specs mean when looking at lithium batteries, and the specs to be aware of are the cycle rates and maximum discharge currents.

[W&KO]

I managed to wade through this swamp last year when I upgraded the Oka house battery from AGM to LiFePO4.
Deano :)

Hi Deano, what brand battery did you select ??

[DeanoH]

Hi Deano, what brand battery did you select ??

What's possibly more important is the process I went through in selection , this takes into account the application/purpose of the installation, the physical and electrical 'environment' it's being installed into as well as overall cost, weight and capacity for future re-configuring. It's worth noting that I'm a retired technician who worked in a low voltage, high current battery environment for many years so I tend to 'over cook the goose' somewhat when dimensioning and building my own stuff [bigsmile1]

In my case the application/purpose of the installation was to upgrade the existing house battery in our Oka mobile home. The original 4 X 66 ah Optimas were now up to 7+ years old (from memory) and even though they were still at 90+% my justification was that they were approaching end of life so needed replacing. That was an excuse really as I was just itching to have a play with LiFePO4 [bigwhistle]

The basic electrical environment in the Oka is a bit different to most 4WD's. From factory it has two 100 ah lead acid batterys, one is a dedicated start battery, the other does everything else. In my case add to this a lead acid house battery of 130+ ah. Vehicle battery coupling is by alternator W+ activated solenoid with a generic Bosch 1485 alternator and 440 watts of solar with separate solar reg. It's worth noting that solar is the primary charging source for the house battery with alternator fed DC-DC convertor as a backup and that the only load on the house battery is an Everkool 145 litre fridge/freezer. The vehicle mounted winch is powered by the two lead acid vehicle batterys and not the house battery. With cable lengths and layout the set up is similar to a 4WD towing a camper trailer.

The physical layout is cabin roof mounted solar of 320 watt being upgraded to 440 watt in conjunction with the battery upgrade, one vehicle battery located just behind each front wheel and the house battery relocated from approx. 300 mm behind the drivers seat to above the drivers side rear wheel.

I figured 200 ah of LiFePO4 was about right for what I wanted, though I found it weird to dimension a system that uses more than 50% SOC from the battery which is something I've never done before as I've mainly dealt with lead acid batterys and is probably why I got such good life out of my Optimas [bigsmile1]

There's good reason with LiFePO4's to have as few cells in the battery as possible so normally a single 200 ah battery would have been my choice but instead I went for 2 X 100 ah batterys so that I could go 24 volt if required. The advantages of 24 volt efficiency wise is significant, especially in high current (>100 amp) applications and cabling costs/size/power loss is reduced for the same outcome. This isn't something that's an issue now but I wanted this option for 'down the track'.

This may seem a bit of waffle or making it harder than it needs to be but I told you I tend to overcook the goose [biggrin] . Anyway, from this I was in the market for 2 X 100 ah LiFePO4 batterys with the capability of being series connected to make 24 volts (not all LiFePO4's have this capability). As Tim points out it's worth reading the specs, 'the devil is in the detail' and even if it's hard to comprehend comparisons can be made between batterys. More is always better [biggrin].

I went with a supplier I'd bought from previously and who has been around for many years. My batterys are the same brand and capacity and similar spec as these but are now a superseded item and [B]NOT the same.


Solarking 12V 100ah Lithium Battery -11KG- Active Cell Balancing - FREE FREIGHT | eBay (https://www.ebay.com.au/itm/Solarking-12V-100ah-Lithium-Battery-11KG-Active-Cell-Balancing-FREE-FREIGHT/324256669456?hash=item4b7f341f10:g:lLgAAOSwl5dfaVO H&frcectupt=true)


They also offered a five year warranty and had a 'smoking good deal' via eBay at the time. I bought two for the same price as one of these [bigsmile][biggrin] and consider them to be a 'middle of the road' choice.

IMO the battery's that Tim was offering at the time were a much better battery and better suited to a proper installation, but for a fiddler like me with low power/current requirements these do the job.

At the end of the day you get what you pay for, only time will tell if I made the right choice [bigsmile1].

The end result (Mark.1) [bigsmile1]


https://www.aulro.com/afvb/attachment.php?attachmentid=164927&d=1601016172


House battery(s) on left, AEG charger for chainsaw battery, 500 watt inverter and leads etc on the bottom. HF main unit and Milwaukee charger at rear. Votronic MPPT reg and DC-DC charger (both with LiFePO4 profiles) on right.

The power distribution panel is mirror imaged left to right with house battery(lithium) on the left and main vehicle (alternator) on the right.


Deano :)

[W&KO]

What's possibly more important is the process I went through in selection , this takes into account the application/purpose of the installation, the physical and electrical 'environment' it's being installed into as well as overall cost, weight and capacity for future re-configuring. It's worth noting that I'm a retired technician who worked in a low voltage, high current battery environment for many years so I tend to 'over cook the goose' somewhat when dimensioning and building my own stuff [bigsmile1]

In my case the application/purpose of the installation was to upgrade the existing house battery in our Oka mobile home. The original 4 X 66 ah Optimas were now up to 7+ years old (from memory) and even though they were still at 90+% my justification was that they were approaching end of life so needed replacing. That was an excuse really as I was just itching to have a play with LiFePO4 [bigwhistle]

The basic electrical environment in the Oka is a bit different to most 4WD's. From factory it has two 100 ah lead acid batterys, one is a dedicated start battery, the other does everything else. In my case add to this a lead acid house battery of 130+ ah. Vehicle battery coupling is by alternator W+ activated solenoid with a generic Bosch 1485 alternator and 440 watts of solar with separate solar reg. It's worth noting that solar is the primary charging source for the house battery with alternator fed DC-DC convertor as a backup and that the only load on the house battery is an Everkool 145 litre fridge/freezer. The vehicle mounted winch is powered by the two lead acid vehicle batterys and not the house battery. With cable lengths and layout the set up is similar to a 4WD towing a camper trailer.

The physical layout is cabin roof mounted solar of 320 watt being upgraded to 440 watt in conjunction with the battery upgrade, one vehicle battery located just behind each front wheel and the house battery relocated from approx. 300 mm behind the drivers seat to above the drivers side rear wheel.

I figured 200 ah of LiFePO4 was about right for what I wanted, though I found it weird to dimension a system that uses more than 50% SOC from the battery which is something I've never done before as I've mainly dealt with lead acid batterys and is probably why I got such good life out of my Optimas [bigsmile1]

There's good reason with LiFePO4's to have as few cells in the battery as possible so normally a single 200 ah battery would have been my choice but instead I went for 2 X 100 ah batterys so that I could go 24 volt if required. The advantages of 24 volt efficiency wise is significant, especially in high current (>100 amp) applications and cabling costs/size/power loss is reduced for the same outcome. This isn't something that's an issue now but I wanted this option for 'down the track'.

This may seem a bit of waffle or making it harder than it needs to be but I told you I tend to overcook the goose [biggrin] . Anyway, from this I was in the market for 2 X 100 ah LiFePO4 batterys with the capability of being series connected to make 24 volts (not all LiFePO4's have this capability). As Tim points out it's worth reading the specs, 'the devil is in the detail' and even if it's hard to comprehend comparisons can be made between batterys. More is always better [biggrin].

I went with a supplier I'd bought from previously and who has been around for many years. My batterys are the same brand and capacity and similar spec as these but are now a superseded item and [B]NOT the same.


Solarking 12V 100ah Lithium Battery -11KG- Active Cell Balancing - FREE FREIGHT | eBay (https://www.ebay.com.au/itm/Solarking-12V-100ah-Lithium-Battery-11KG-Active-Cell-Balancing-FREE-FREIGHT/324256669456?hash=item4b7f341f10:g:lLgAAOSwl5dfaVO H&frcectupt=true)


They also offered a five year warranty and had a 'smoking good deal' via eBay at the time. I bought two for the same price as one of these [bigsmile][biggrin] and consider them to be a 'middle of the road' choice.

IMO the battery's that Tim was offering at the time were a much better battery and better suited to a proper installation, but for a fiddler like me with low power/current requirements these do the job.

At the end of the day you get what you pay for, only time will tell if I made the right choice [bigsmile1].

The end result (Mark.1) [bigsmile1]


https://www.aulro.com/afvb/attachments/communications-car-audio-and-electronics/164927d1601016172-swapping-lithium-power-panel.jpg


House battery(s) on left, AEG charger for chainsaw battery, 500 watt inverter and leads etc on the bottom. HF main unit and Milwaukee charger at rear. Votronic MPPT reg and DC-DC charger (both with LiFePO4 profiles) on right.

The power distribution panel is mirror imaged left to right with house battery(lithium) on the left and main vehicle (alternator) on the right.


Deano :)

Thanks for the detailed reply......

I research enough to satisfy my interest....in the end got tied of people questioning why go to this trouble to use induction cooktops. The other thing that’s frustrating is people view on the investment I’ve chosen.

Ended up chatting to a few people that had similar installs with gear I was interested in...feedback was it worked, suited their needs and they were happy with the spend. I pretty much based my install around theirs.

I’m happy, it’s works and suits our needs just fine. Had a couple of hiccups on the test, root cause was the installer, after sales support from manufacturer has been really good. Upgraded two cables, removed a fuse and isolator and made an adjustment on the shunt. I learnt some and so did the installer.

I like your comment that switching isn’t quite as simple as it’s generally made out to be

[drivesafe]

Hi again Deano and the batteries you have, for what you paid, are fine.

The two brands of batteries I was referring to have specs that are NOT as good as yours, yet one was $1499 and the other was $1846.

As posted, anyone considering buying Lithium batteries, do a lot of research before you buy.

And “BRAND NAMES” mean very little.

[W&KO]

Any update