Thread: Battery talk... Come in Tim.

Hi and thanks JayTee, I had not seen that video.

It is the typical Lithium Battery B/S sales pitch.

First and foremost, find a single lead acid battery manufacturer that states their batteries should not be discharged below 50% SoC. They are either 20% or many of the newer AGMs are 0%.

Another point, base on the specs of the Redarc lithium batteries, which are just average, there are far better lithium batteries for a fraction of the price. For example, SolarKing are a fraction of the cost and have better specs.

There is lots more that that video incorrectly covers.

Originally Posted by drivesafe

Hi and thanks JayTee, I had not seen that video.

It is the typical Lithium Battery B/S sales pitch.

First and foremost, find a single lead acid battery manufacturer that states their batteries should not be discharged below 50% SoC. They are either 20% or many of the newer AGMs are 0%.

Another point, base on the specs of the Redarc lithium batteries, which are just average, there are far better lithium batteries for a fraction of the price. For example, SolarKing are a fraction of the cost and have better specs.

There is lots more that that video incorrectly covers.

Like I said, I wasn't going to say a word, but you have confirmed what I thought initially. Sales pitch mostly.

Thanks for the heads up on SolarKing.

That video only gives half the story on a number of subjects.

For instants, the fridge runs 100% longer on the lithium battery then it does on the AGM???????????????????????????

This actually has more to do with the quality of the fridge compressor than the battery type.

I can not comment on that brand of fridge as I have never work with them.

But, while you would get slightly more operating time when using a lithium battery, it would be so insignificant and the additional run time would be lost in the fact that the lithium would take at least 3 times longer driving time to recharge the battery via a DC/DC device.

He stated that his two AGMs only lasted 3 years and I bet ( while not stated ) that they were being charged by a DC/DC device.

As such, the AGMs were probably never decently charge after each drive.

Because he has a Toyota, which has a VARIABLE Voltage ( NOT a SMART ) alternator, he could have easily charged his AGMs directly ( via a simple VSR ) off his alternator and I bet they would have lasted much longer.

When compared to using one of my isolators, it would actually be a huge step backwards to go to a Lithium battery setup.

Over 4 years ago I fitted 4x 100AH AGM batteries ( 2 in the van and 2 in the 79 Series) that are charged via solar alone (400w on the van and 200w on the Toyota), They are still working just as good as the day I fitted them
I also recently fitted a 160w panel and a 110AH AGM battery to my D2a which again is solely powered/charged via solar.

The reason why I have chosen to Not have the batteries charged via the vehicles alternator is that I want to keep the 12v system as simple and as bullet proof as it can be.

I presume that the batteries getting fully charged Every day via the solar panals instead of sitting idle until the engine is started Is helping to keep them in good order.

My 120AH AGM in the RH rear storage bin in my D2a is still working fine after 11 Years. Granted it probably has less than 2/3 of the original capacity as I don't baby it !

But it only gets charged with with alternator via one of Tims SC80's.

Simple setup and ultra reliable.

Hi Simon, what is the brand of you AGM?

Hi Tim,

Its a Neuton Power AGM. 120AH and weighs about 39 kg so not easy to get into the rear bin!


Next battery I’ll try and find something lighter, possibly and affordable Lithium I think which should be around 10 Kg for the same usable AH?

Originally Posted by drivesafe

Hi Simon, what is the brand of you AGM?

Well, I got about half way through this video and gave it away ........................................... Talk about a little bit of knowledge is a dangerous thing. I reckon this bloke is probably well intentioned in spite of his obvious sponsorship by Redarc but he's clearly got no understanding of lead acid battery chemistry, imagine lead sulphate forming on the plates, shock horror . How the hell does he think a lead acid battery works ? And a 50% discharge limit, what a load of crap. Sure, the deeper you discharge a battery the shorter its life, no surprises there. Personally I use 11.7 volts or around 30% SOC as my max no worries discharge limit for lead acid. IMO re-charging rate is more likely to ruin a deeply discharged lead acid battery than its actual discharge level, slow is good

It goes on, Lithium batterys have greater discharge current than lead acid, bull ****. Try running your winch of your Lithiums and see how well it goes. As for longevity, I finally swapped out my Optima AGM's after 7 years and they were still at 80+%.

No mention what so ever about charge current limiting for Lithiums (maybe in second half of video?) and possible alternator damage, though a DC-DC is basically essential IMO to overcome this potential issue but rarely explained or discussed.

It goes on, $1900 for a 100 AH Lithium, you've got to be on Meth to swallow this one. FFS you'll pick up a PAIR of Solar King 100 AH Lithiums today for under $1200 and with a five year warranty. I bought a two of these a couple of years ago and they've been great for my Oka house battery. With 400+ watts of solar panels, a quality solar controller and DC-DC charger (rarely needed) the whole lot costs about the same as one extremely overpriced Redarc 100 AH Lithium battery.

Deano