Charging Lithium Batteries Vs Charging AGM Batteries

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I'm told one of the advantages of the lithium battery is that it will accept a much higher charge rate than the equivalent AGM battery. My Redarc charger is not designed for lithium but my batteries have an inbuilt battery management system so I'm counting on that looking after the charge rate.
Did you put Lithiums in Phil?
If so what type, price etc?
 
I'm told one of the advantages of the lithium battery is that it will accept a much higher charge rate than the equivalent AGM battery. My Redarc charger is not designed for lithium but my batteries have an inbuilt battery management system so I'm counting on that looking after the charge rate.
Yeah AGM is Good if you have the Sun Hours and a lot better than FLA's when it comes to charging speed,

I went away friday and I took 2 Lithium portapacks and a 120w foldout 4 piece cheap solar panel and just to stuff things up I plugged the little Dometic fridge in to one of the Packs and the I also plugged in the 35L Snomaster set at -22*c and switched it to High speed mode Flattening the lithium pack by 12% and the little 120w panel still still managed to power both fridges at the same time as well as charge the 40Ah / 512Wh lithium pack, even with limited sun and it took it just over 2 hour to charge while running both a fridge and one as a freezer.

So that is a win of sorts, I went off friday night and came home at 5am monday morning.
 
I bought two SolarKing 120AH batteries last May for $653.46 plus tax each. Since then we've had a couple of months in the Pilbara prospecting and then a couple of months to Darwin and Arnhem Land. They are charged by the Redarc BCDC2420 with both solar and alternator charge. The Redarc will only handle 12v panels so I still have the Morning Star solar charger coupled to the 24v 250w solar panel connected as well but it runs into overcharge mode regularly and has to be reset to work again.

Well that was until last week when the 24v panel had to go to make space for the new rooftop air-conditioner. Now I have two 110w GE panels mounted on top of the trailer and wired through the existing Morning Star solar controller. I could have wired the two 110w GE panels through the Redarc but I like having the second solar system as a backup. I was quite happy when I plugged the Dometic Harrier Lite air conditioner into the 24v 1500w inverter and it ran sweetly. I doubt the two lithium batteries will keep it going for long but if we're in stinking hot conditions like the Darwin trip then I can run the Dometic AC while we travel.

Oh, one problem with the lithium batteries. They are useless for cranking. I had an intermittent dead bus start battery while we were away and it took me a couple of weeks to track down the problem. I was caught a couple of times with flat batteries and flicked the lithium batteries in to start. You get one instant crank (and the Isuzu starts instantly) and the lithium batteries spit the dummy. All systems show no battery connection at all and it takes some time for them to come to life again. The average engine would not start in the moment it takes for the batteries to drop out. If I'd know how bad they were I'd have altered the battery mounting and purchased the 150AH batteries that can be used for cranking.
 
I bought two SolarKing 120AH batteries last May for $653.46 plus tax each. Since then we've had a couple of months in the Pilbara prospecting and then a couple of months to Darwin and Arnhem Land. They are charged by the Redarc BCDC2420 with both solar and alternator charge. The Redarc will only handle 12v panels so I still have the Morning Star solar charger coupled to the 24v 250w solar panel connected as well but it runs into overcharge mode regularly and has to be reset to work again.

Well that was until last week when the 24v panel had to go to make space for the new rooftop air-conditioner. Now I have two 110w GE panels mounted on top of the trailer and wired through the existing Morning Star solar controller. I could have wired the two 110w GE panels through the Redarc but I like having the second solar system as a backup. I was quite happy when I plugged the Dometic Harrier Lite air conditioner into the 24v 1500w inverter and it ran sweetly. I doubt the two lithium batteries will keep it going for long but if we're in stinking hot conditions like the Darwin trip then I can run the Dometic AC while we travel.

Oh, one problem with the lithium batteries. They are useless for cranking. I had an intermittent dead bus start battery while we were away and it took me a couple of weeks to track down the problem. I was caught a couple of times with flat batteries and flicked the lithium batteries in to start. You get one instant crank (and the Isuzu starts instantly) and the lithium batteries spit the dummy. All systems show no battery connection at all and it takes some time for them to come to life again. The average engine would not start in the moment it takes for the batteries to drop out. If I'd know how bad they were I'd have altered the battery mounting and purchased the 150AH batteries that can be used for cranking.
My Noco GB150 Pro has little Lithium Cells inside it and because they are small it will run a small fridge for about 4 hours yet it has the power to put out up to 4000A for starting big Diesel and Petrol engines up to 10 Litre+.

Lithium can be used as a Starter battery and some vehicles have them, Most companies won't supply them as standard because of the cost, If a Lithium Battery costs $1000 in the shops you can bet Car Dealers are going to charge you around $2300 for the same battery,

The only down side to Lithium is extreme cold and extreme heat,

The best thing about the pre-made portapacks is they have all the fixings and sockets needed for going off grid and they never over charge and once the SOC gets up around 90/95% you can see the Watts input start to drop and when they are charged they just shut them selves off,

Lithium is not for everyone, Camping in my Van it's a winner, Off-grid living it also works, where it really makes a big impact is you can flatten and charge it 3 or 4 hours and be ready to go again, and what your fridge etc uses at night you can put back within an hour or so where as lead acid it can take 4, 5, or 6 hours to put the power back in

I managed to replace the power i used at night in 90 minutes In very foggy cloudy conditions with zero Sun and when the sun did appear as the sun was going down I was still getting 40-50w and once it had gone down I was still getting 30w So it was putting out power all the time there was daylight.
 
I'm told one of the advantages of the lithium battery is that it will accept a much higher charge rate than the equivalent AGM battery. My Redarc charger is not designed for lithium but my batteries have an inbuilt battery management system so I'm counting on that looking after the charge rate.
AGM (lead) accepts 60% of the charge put in, Lithium accepts 95%.
Battery management system is ok for a 240v charger set to agm but NOT a solar regulator that doesn't have a Lithium option. If that Redarc you're using is a solar regulator - kiss your Lithium battery goodbye, might take a while but it will kill it eventually
 
I bought two SolarKing 120AH batteries last May for $653.46 plus tax each. Since then we've had a couple of months in the Pilbara prospecting and then a couple of months to Darwin and Arnhem Land. They are charged by the Redarc BCDC2420 with both solar and alternator charge. The Redarc will only handle 12v panels so I still have the Morning Star solar charger coupled to the 24v 250w solar panel connected as well but it runs into overcharge mode regularly and has to be reset to work again.

Well that was until last week when the 24v panel had to go to make space for the new rooftop air-conditioner. Now I have two 110w GE panels mounted on top of the trailer and wired through the existing Morning Star solar controller. I could have wired the two 110w GE panels through the Redarc but I like having the second solar system as a backup. I was quite happy when I plugged the Dometic Harrier Lite air conditioner into the 24v 1500w inverter and it ran sweetly. I doubt the two lithium batteries will keep it going for long but if we're in stinking hot conditions like the Darwin trip then I can run the Dometic AC while we travel.

Oh, one problem with the lithium batteries. They are useless for cranking. I had an intermittent dead bus start battery while we were away and it took me a couple of weeks to track down the problem. I was caught a couple of times with flat batteries and flicked the lithium batteries in to start. You get one instant crank (and the Isuzu starts instantly) and the lithium batteries spit the dummy. All systems show no battery connection at all and it takes some time for them to come to life again. The average engine would not start in the moment it takes for the batteries to drop out. If I'd know how bad they were I'd have altered the battery mounting and purchased the 150AH batteries that can be used for cranking.
Get one of these

OzCharge RM1000 Rescue Mate​

I have a 200 series landcruiser 4.5L V8 Diesel and it stated that when I had a flat battery. It's like a box of magic, there's no battery in it to keep charged, you simply hook up to your own flat battery (needs to have at least 5v in it) wait for it to charge (about a MINUTE or two) & it starts your engine MAGIC!
 
Read up on temp effects above 45C for lithium and you may find in WA an FNQ where ambient temps can easily reach that, or for under bonnet duel batt set ups your better to stick with AGM
 
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AGM (lead) accepts 60% of the charge put in, Lithium accepts 95%.
Battery management system is ok for a 240v charger set to agm but NOT a solar regulator that doesn't have a Lithium option. If that Redarc you're using is a solar regulator - kiss your Lithium battery goodbye, might take a while but it will kill it eventually

I guess we'll just have to wait and see. I discussed it with the guys from Redarc and Access 12v Warehouse before I fitted it and they both said that I might not achieve maximum charge but neither had the opinion that it would be harmful to the batteries.
 
The BMS os a management system..it monitors and regulates the charge going into the lithium cells from your charger. So if your charger is outside the proper charging parameters of the cells the BMS will only those rates. It will not boost or lower those charge rates to compensate for the lower or higher rates..it will just shut down..as the BMS is designed to do. Then depending on the type of BMS, some of the upper market ones have a balancing programme which constantly balances the cells whilst charging. So in a way a lithium will accept charge from a non lithium profile charge..but the expected working life span of the cells is reduced. Hence you may get around this buy purchasing lower entry lithium batteries..ie below $800 and get five years..replace it when it dies..you might only get three and they are under warranty…but be careful read the fine print..because some warranties..stipulate that the battery MUST be charged via a lithium profile charger or the warranty is void…eventhough in their marketing bull they have said you can charge without a lithium profile charger. So to get the best operating life and warranty coverage for your purchase it’s best to use a proper lithium profile charger.
Then there is the issue of underbonnet lithium cranking batteries. The manufactures reiterate the fact that lithium batteries do not like heat by their warranties..DCS state that the warranty of their batteries when used as a cranking battery positioned under the bonnet is 3 years..where as used in other methods 5 years..so even they in their warranty acknowledge lithium batteries do not like heat and it degrades their working life. If blokes want to throw away $2K every 3 years when a $300 cranking battery will do the same..that’s the simple fact..you do not have to like it!
Then if blokes are worrying about a 15kg weight saving on their touring vehicle plus drag around airfryers, induction cooktops and all the flash gear and are willing to fork out $2K..I’m on the wrong merry go round.
 
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AGM (lead) accepts 60% of the charge put in, Lithium accepts 95%.
Battery management system is ok for a 240v charger set to agm but NOT a solar regulator that doesn't have a Lithium option. If that Redarc you're using is a solar regulator - kiss your Lithium battery goodbye, might take a while but it will kill it eventually
When it comes to AGM Batteries Condor22 is the Guru,

Yes an AGM might accept 60% but most AGM makers recommend 10 to 20% and the maximum you would ever want to use is about 25% or you will shorten the life of the battery,

Any Battery that has a managment system is going to a pain to charge unless the charger has the matching charging profiles, Where AGM's when completely flat most smart chargers will not charge them and the only way to bypass this issue is to connect another battery to the flat battery in paralelle and connect the Charger to the full battery and when the AGM starts to accept a bit of charge you can then disconnect the 2md battery and charge the AGM as mormal with a smart chsrger.
 
The BMS os a management system..it monitors and regulates the charge going into the lithium cells from your charger. So if you a charger that is outside the proper charging parameters of the cells the BMS will only work with those. It will not boost or lower those charge rates, depending on the type of BMS, some of the upper market ones have a balancing programme which constantly balances the cells whilst charging. So in a way a lithium will accept charge from a non lithium profile charge..but the expected working life span of the cells is reduced. Hence you may get around this buy purchasing lower entry lithium batteries..ie below $800 and get five years..you might only get three and they are under warranty…but be careful read the fine print..because some warranties..stipulate that the battery MUST be charged via a lithium profile charger or the warranty is void…eventhough in their marketing bull they have said you can charge without a lithium profile charger. So to get the best operating life and warranty coverage for your purchase it’s best to use a proper lithium profile charger. If you want to live on the wild side go for it..keep using a non lithium profile charger..
A lot of Lithium batteries often come with a matching charger like the Lithium power stations do,

Also you can Program Victron MPPT controllers to suit AGM and Lithium profiles, All 4 of my Lithium SoGens have MPPT Controllers built in so all you have to do is plug the Solar Panels directly in to them and as long as you don't exceed the maximum Voltage all is fime and if you exceed it Max Voltage you just have to reset it and remove one panel.
 
When it comes to AGM Batteries Condor22 is the Guru,

Yes an AGM might accept 60% but most AGM makers recommend 10 to 20% and the maximum you would ever want to use is about 25% or you will shorten the life of the battery,

Any Battery that has a managment system is going to a pain to charge unless the charger has the matching charging profiles, Where AGM's when completely flat most smart chargers will not charge them and the only way to bypass this issue is to connect another battery to the flat battery in paralelle and connect the Charger to the full battery and when the AGM starts to accept a bit of charge you can then disconnect the 2md battery and charge the AGM as mormal with a smart chsrger.
I don't think we're on the same page
60% = for every 10amps pushed into the AGM 6amps will be usable as 4amps gets resisted during the process of charging, whereas Lithium you'll get 95% or 9.5 usable amps for every 10 amps you push in.
So Lithium will charge a lot faster than lead which is a lot of fuel saved if using a generator also consideration on the amount of solar panels required for each which brings us back to weight adding it on or taking it off. (I'm going off on a tangent here sorry)
I run 2 x 240ah Lithium 25kg each = 50kg. Usable amps @ 80% = 384 amps

To get 384 amps usable power from lead (agm) I'd need 768 amps total as 50% drained is considered flat. I would need a bit more than 6 x 120ah agm batteries @ 33kg each 198kg I'm saving 148kg by using Lithium + consideration on solar panel saving.
 
I don't think we're on the same page
60% = for every 10amps pushed into the AGM 6amps will be usable as 4amps gets resisted during the process of charging, whereas Lithium you'll get 95% or 9.5 usable amps for every 10 amps you push in.
So Lithium will charge a lot faster than lead which is a lot of fuel saved if using a generator also consideration on the amount of solar panels required for each which brings us back to weight adding it on or taking it off. (I'm going off on a tangent here sorry)
I run 2 x 240ah Lithium 25kg each = 50kg. Usable amps @ 80% = 384 amps

To get 384 amps usable power from lead (agm) I'd need 768 amps total as 50% drained is considered flat. I would need a bit more than 6 x 120ah agm batteries @ 33kg each 198kg I'm saving 148kg by using Lithium + consideration on solar panel saving.
Yeah thats close to the figures I worked out when comparing Lithium to FLA's or AGM's

I have 4 Lithium Packs, The 1800wh @ 14.6v works out to be around 123.28Ah and at 12.8v works out at 140.62Ah, The other 3 are 512Wh which gives me over 3300Wh which is more than enough for now, But I do plan on adding 2 more 2400Wh packs soon which will give me over 7.6Kw.
 
I advocate leaving an AGM on charge when not used. However, you need a good quality charger to do that. In my current situation, I have mains power to the van, the charger floats the battery at 13.2 V and once a month puts it into a brief full charge cycle to condition it.

However, I'm moving home in a few months and the van will be in an area without power access, so I'll leave the solar panels on. The Victron has been reprogrammed to float at the same 13.2 V.

If Jaros's battery lost 5% a month = 6.5 AH, the charger will recharge it. If he left it 6 months it might lose 39 AH, his charger will still charge it, but just take longer to bring it back to full, compared to say my charger. I agree, his charger could be bigger and would be better if it were, but, what he has will work. :)

I do not dispute the available power in a comparable Lithium battery, or the weight saving. It all boils down to what you have, what you need and how deep your pockets are.
:)

I am looking to put a 100AH Lithium into my caravan before I next use it. However, my mains charger will be ok as it a. has a lithium profile, but I will use power supply mode. and b. my mate will reprogram the Victron solar controller to suit. I don't use DC-DC in the van.
I run 3 x100ah lithium batts @13kg each x 2 /300w solar panels on a victron 10amp dc dc charger and on my alternator 80amp its control solely on my redarc dc dc1220d two great chargers and run a 250 samsung inverter fridge 24/7 and only use 28ah overnight an recharged by mid morning on a controlled 8 amp feed the usage will increase once we hit the road again👍🚐
 
Yeah thats close to the figures I worked out when comparing Lithium to FLA's or AGM's

I have 4 Lithium Packs, The 1800wh @ 14.6v works out to be around 123.28Ah and at 12.8v works out at 140.62Ah, The other 3 are 512Wh which gives me over 3300Wh which is more than enough for now, But I do plan on adding 2 more 2400Wh packs soon which will give me over 7.6Kw.
RR,
Any chance you can stick to either AH or Wh to provide clarity and avoid confusion?
 
RR,
Any chance you can stick to either AH or Wh to provide clarity and avoid confusion?
I put both there because in the past some folks wanted Ah and then others wanted Wh, So I put Both sets of figures so everyone would be happy,

I guess the easy way round it is for me to leave out the Ah and the Wh and just write the numbers and let people decide what they mean,,

😆🤣🤣🤣🤣🤣🤣🤣
 
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Probably just be easier to leave all the waffle out ? You can build a system that will keep your beers cold, steaks frozen and run your water pump for under a thousand dollars and will do so for a month off grid as long as not over cast for more than three days in succession. I do in FNQ and yes I know eastern states have a lot less sunlight but ambient temps also being much lower your fridges (fridges being main current draw) are running way less by comparison. If you need 6000 meg bittles of power and four batteries with composite diodic charge rates that compensate for ambient temp changes of more than 2 degrees in 5 minutes when the stoich rate drifts outside it's best......................................... you probably have taken to much shit with you and shouldn't be out camping ? 🤣🤣🤣🤣🤣🤣:cool:
 
Probably just be easier to leave all the waffle out ? You can build a system that will keep your beers cold, steaks frozen and run your water pump for under a thousand dollars and will do so for a month off grid as long as not over cast for more than three days in succession. I do in FNQ and yes I know eastern states have a lot less sunlight but ambient temps also being much lower your fridges (fridges being main current draw) are running way less by comparison. If you need 6000 meg bittles of power and four batteries with composite diodic charge rates that compensate for ambient temp changes of more than 2 degrees in 5 minutes when the stoich rate drifts outside it's best......................................... you probably have taken to much shit with you and shouldn't be out camping ? 🤣🤣🤣🤣🤣🤣:cool:
Yeah it's really easy to go OTT with the clobber we haul, I've thinned mine down and now I am looking at a small Caravan or a Teardrop trailer to carry any excess, But the main reason is to have something that is thermal lined for these cold winters,

I ditched the 3x 115Ah deep cycle batteries and a 100w solar panel And a brand new Victron 100/20 charge controller last weekend, gave em to someone else to use,. There is no point in me having all that space if I'm gonna haul stuff I don't need, 👍
 
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