Thread: Replacing cranking and yellow top battery with Lithium's?

FWIW..

Lithium batteries are not a drop in solution for cranking batteries (yet) they require charging and monitoring regimes that are outside of the realm of easily 90%+ of all vehicles out there today.

Coupled with the appropriate charge managers You could easily and reliably use them for every other aspect of operating a vehicle including using a small DC-DC charger to pump charge the main cranking battery or even direct jump start from (like say a lithium jump start pack does).

as Drive safe has already pointed out the issue is the flatter steeper curved discharge profile of the battery which maintains a near constant voltage until the last few amps of the battery that is the main issue to keep you from wanting to use one as a starter. The second being that as the battery begins to fail it still maintains the same constant voltage profile under load but it wont deliver for as long. This means short of a catastrophic failure you dont get a lot of warning about the battery going bad, and a catastrophic failure is unhealthily toxic and "oh, the cars on fire" levels of bad for your health.

Lithiums also do not react well to high charge currents which (assuming you let it get flat enough for this to happen) is going to happen if the lithium is down near flat and the alternator is either old school (in which case it will pump every amp it can until the voltage gets to regulation point) or computer permitted to run at max amps to put the initial charge into the battery (which can mean the charge voltage will go above the nominal charge rate for your lithium battery as well as over amps) the oddball curve compared to lead acid batteries also suffers from absorbsion lag, if you charge em fast the cell voltage comes up quickly but then if you dont maintain a high voltage but low current charge to them they may only be at 60-70% of their capacity, at normal automotive lead acid charge rates this could be as little as 30-50% (think short run driving, just to the shops and back type stuff, in winter at night)

IMHO, FWIW
Well looked after when it comes to bang for your buck and ignoring unexpected failure (dropped it, set fire to it, some one shot it anything thats not a natural death by attritional use type deal) the rough order in terms of dollar value for stored energy over time with no other considerations...

Cheap flooded cells are in front because they are cheap to buy and easy to maintain, in perfect conditions they last for nearly as long as a lithium or AGM should in average conditions. in average conditions the cheap cost multiplied by the 3 year average useful life puts them ahead in terms of cost
Lithiums are in second the higher cost is offset by the extended life in average conditions they should last about 10 years, in perfect conditions and depending on use theoretically they might make 25 + years in which case, miles in front.
AGMs are in third with the cost and slightly longer life over a cheap flooded cell making them more expensive.

But you have to weigh in all the pros and cons. You're not all going to sit your batteries in a perfectly controlled environment with perfect use conditions. The mechanical abuse an AGM can take over a cheap flooded cell battery will put the AGM ahead in short order if you shake a flooded cell battery apart every 3 months. If you cant afford the weight or space required to mount 1000AH of flooded cell batteries (or agm) then lithium takes a massive lead.

Would I run lithium? Yes, if I could afford it, In a heart beat but, I have a solar system that can be relied upon to keep top up charge going to the battery and I very rarely do short runs in conditions that are adverse conditions for the battery. It also helps that if I'm desperate enough I need absolutely no voltage anywhere on the vehicle and I can get it to start and drive normally. (actually that applies to all of my vehicles, the motor bike included)

Hi Dave and there is some very good advantages to using lithium batteries in caravans but it still comes back to whether a user is actually going to get the benefit of the advantages lithium’s offer over conventional batteries.

This is why everyone considering caravan use and more specifically battery use in these caravans, needs to do a lot of research about what they will personally gain or potentially loose, by swapping to lithium batteries.

People are unlikely to “loose” by going to lithium’s from a usage prospective, but their pockets could take a seriously huge hit with no real gain, and this is where people need to look hard at what they actually want from their battery setup.

The biggest single problem I see for someone trying to decide whether to make the change is the incredible amount of misleading info out there about lithium battery capabilities.

The amount of times “individuals” make claims about ”how much better” their system now works since they changed to lithium batteries, when in actual fact, they have gained no real advantage and the change has actually done nothing more than make them “feel Good”.

There needs to be far more True data based discussion on this subject so people considering the potential of changing, can get a realistic idea of whether a change is to their specific advantage.

Originally Posted by W&KO

For your caravan, my thoughts

I kinda gave up on researching, well Once I knew roughly what I wanted I decided to talk to those that had the brands i was thinking on using and get their real life feedback.

Apart from a DC-DC I believe you also need a couple of other items depending on which brands you purchase.

Shunt/low voltage cut out, given lithium’s hold a constant voltage you need watch capacity in % to know charge state of battery. I believe mine will cut out at 18% therefore I have 182ah usable. Actually that’s the only thing other than a battery charger with a lithium profile. I’m not carrying a battery charger.

If you already have solar on the van and a quality regulator than you may get to keep using it....it depends on which DC-DC you choose, some preference the alternator, others take charge from both solar and alternator and some I believe preference solar over alternator. My DC-DC preferences the alternator, even though it has a solar input I still run my solar through a separate controller so that my battery receives charge from both sources.

Battery, understand charge rate, mine only accepts 60ah and max discharge rate, mine has 200a constant discharge which is what I needed as we ditched gas and only use an induction cooktop.

Costs, lithium appears to expensive and there are comparisons around that make it look pretty affordable over the life of the battery when compared to AGM. I do know it’s a big investment regardless.

We are not towing and are setting up for two years on the road.....at the moment it looks like my system now has a fair bit of fat in it. went from a 110ah AGM to a 200 lithium which has pretty much tripled my capacity for no real extra weight. I also have more efficient solar. On the flip side it’s nice not having to watch SoC and weather.

Keep us posted on your van upgrade.

The van has all quality Victron gear, Blue Solar Controller and 240v Blue smart charger. Both have bluetooth and Lithium profiles available. All van 12 volt goes through a Projecta 12v low voltage cutout to protect batteries from getting too discharged. I can set jumpers on that to set low voltage cutout. I will get (probably) a victron DC to DC charger. I would think all the victron devices should work together. Still researching but this seems the way to go.

I appreciate your logic and thoughts. Lithium is still favoured in my mind. I currently run 2 (6 volt)x 250 Ah Full Rivers wired in series. They seriously have to be about 35-40kg each. If I went to 100Ah Lithiums they are 13kg each and physical size is almost identical so no manufacturing to fit them in and I save about 45kg of mass. So this is the way I am leaning but still open to ideas. No mad rush.

Originally Posted by Briar

The van has all quality Victron gear, Blue Solar Controller and 240v Blue smart charger. Both have bluetooth and Lithium profiles available. All van 12 volt goes through a Projecta 12v low voltage cutout to protect batteries from getting too discharged. I can set jumpers on that to set low voltage cutout. I will get (probably) a victron DC to DC charger. I would think all the victron devices should work together. Still researching but this seems the way to go.

I appreciate your logic and thoughts. Lithium is still favoured in my mind. I currently run 2 (6 volt)x 250 Ah Full Rivers wired in series. They seriously have to be about 35-40kg each. If I went to 100Ah Lithiums they are 13kg each and physical size is almost identical so no manufacturing to fit them in and I save about 45kg of mass. So this is the way I am leaning but still open to ideas. No mad rush.

With your existing equipment Briar, you are pretty well setup for a comparatively less expensive changeover if you go that way.

Again, do make sure you research the different lithium batteries on the market if you do decide to change to them.

I no longer sell lithium batteries otherwise I would have been able to offer you what are probable the best, dollar for dollar, lithium batteries on the Australian market.

Seriously though, do your homework before buying, as there are some crap batteries on the market and some are well known brands that are proving to be nothing more than elcheapo batteries, marketed under well known brand names, but are failing after very short periods of use.

BTW Briar, as you posted, if you are not in a hurry, keep an eye on caravan makers in Victoria.

As they get over the effects of the lock-down, there will be at least two new All-Electric caravans coming on the market and one of them is going out of their way to use as much Australian Made content as they can.

They are also assembling their own lithium batteries using Japanese Lithium cell and quite a few other up-market products.

Some of these products could be very interesting to the RV industry as a whole.

If you look at the Will Prouse You tube site , he has tested Renolgy batteries in the States against others and found them to meet their AH claims.

The brands sold in Australia are generally not the same as in the USA but this is one that is.

I am now deeply suspicious of Ebay Lithium Battery AH claims after experience by a friend and also an earlier Ebay "scandal" involving a cheap seller of lithium batteries who was eventually delisted but had 100% positive feedback even though they had many disgruntled customers.

Regards PhilipA

DIY Solar Power with Will Prowse - YouTube

Originally Posted by drivesafe

Hi Dave and there is some very good advantages to using lithium batteries in caravans but it still comes back to whether a user is actually going to get the benefit of the advantages lithium’s offer over conventional batteries.

This is why everyone considering caravan use and more specifically battery use in these caravans, needs to do a lot of research about what they will personally gain or potentially loose, by swapping to lithium batteries.

People are unlikely to “loose” by going to lithium’s from a usage prospective, but their pockets could take a seriously huge hit with no real gain, and this is where people need to look hard at what they actually want from their battery setup.

The biggest single problem I see for someone trying to decide whether to make the change is the incredible amount of misleading info out there about lithium battery capabilities.

The amount of times “individuals” make claims about ”how much better” their system now works since they changed to lithium batteries, when in actual fact, they have gained no real advantage and the change has actually done nothing more than make them “feel Good”.

There needs to be far more True data based discussion on this subject so people considering the potential of changing, can get a realistic idea of whether a change is to their specific advantage.

For Traxide Tim / Drivesafe - ?
So, I like any number of others have a pretty standard modern battery set-up in my 4 year old van with a well known BMS (name escapes me at the moment, and van is parked elsewhere), and the AGM battery has just given up the ghost, despite being semi permanently fitted to a 120W solar panel when parked up.

We try to do at least 3 - 4 trips a year, of varying lengths and towing with the D4, with some off grid, but never anywhere near dropping the battery to 50% (we take another AGM if we plan any more than a couple of days away from power).

I would appreciate any comments, but suspect that in our situation, and similar to any number of others, moving to Lithium would currently be a lineball decision, given (i) we are getting on and have an absolute max of 10 years still capable to tow if all goes well health-wise, and (ii) we would need a DC to DC charger plus whatever else upgrading factored in.

Hi Gavin and any idea of the brand of AGMs you have now?