AGM Battery advise in 2019

[pteck]

Originally Posted by uncle_bob

Hi

Lithium technology has been out there for a couple of decades at this point. The same chemistry that was "best" back in the 90's is still going strong today. Even if some magic this or that came out in 10 years - would you want to actually invest in it? You likely would go with the stuff that had (by then) 30 years behind it. Indeed you could wait another 20 years past that point. I for one will not be shopping for batteries 30 years from now ....

Bob

If you want to talk about "best", you should talk about a battery technology that has been with us since the 1800s, and is still with us in significant application and volume. Today, it still represents some of the best (value) in batteries. That's the lead acid battery in its various forms.

I say this tongue and cheek as I recognized best is an interpretation, subject to how one uses their batteries. I know how you might to try to justify its better value based on discharge cycles and lifetime units of energy, it's great 1c high draw abilities, etc. Yet lithium has its limitations too where it's not the best in cost, temperature handling, selfish BMS low SOC cut-off as it doesn't have lead acids ability for emergency reserves, etc. Just trying to paint a more balanced picture.

AGMs are perhaps a best in a balance of cost vs. capability.

I personally use flooded lead acids as I find them best for low power draws. I have a second bank of lithium to power the high draw 120V stuff. 300Ah for $1k invested. That, to me, sounds like best in some way.

[uncle_bob]

Originally Posted by pteck

If you want to talk about "best", you should talk about a battery technology that has been with us since the 1800s, and is still with us in significant application and volume. Today, it still represents some of the best (value) in batteries. That's the lead acid battery in its various forms.

I say this tongue and cheek as I recognized best is an interpretation, subject to how one uses their batteries. I know how you might to try to justify its better value based on discharge cycles and lifetime units of energy, it's great 1c high draw abilities, etc. Yet lithium has its limitations too where it's not the best in cost, temperature handling, selfish BMS low SOC cut-off as it doesn't have lead acids ability for emergency reserves, etc. Just trying to paint a more balanced picture.

AGMs are perhaps a best in a balance of cost vs. capability.

I personally use flooded lead acids as I find them best for low power draws. I have a second bank of lithium to power the high draw 120V stuff. 300Ah for $1k invested. That, to me, sounds like best in some way.

Hi

The point was only that expecting some sort of radical "improvement" in lithiums over the next few years is probably not a good strategy. The technology is more mature than a lot of people give it credit for being.

Bob

[pteck]

Originally Posted by uncle_bob

Hi

The point was only that expecting some sort of radical "improvement" in lithiums over the next few years is probably not a good strategy. The technology is more mature than a lot of people give it credit for being.

Bob

I agree that lithium is quite mature at this time.

I do hope for radical changes still. Being an order of magnitude more expensive than FLAs, leaves lots of opportunity for improvement.

[lsbrodsky]

Originally Posted by pteck

I agree that lithium is quite mature at this time.

I do hope for radical changes still. Being an order of magnitude more expensive than FLAs, leaves lots of opportunity for improvement.

I am sorry to dissent but I think lead-acid cells are like buggy whips. IMHO, their only advantage is cost. This 19th century technology. While I will admit that AGM's have eliminated some of the inferiorities, if you can afford an Airstream, you can afford a better electrical system. "Better" means the best available battery technology, to me, and LiFePO4 has shown itself to be that technology. Look at the junk Airstream has added to trailers today, maybe justifying price increases, but they do not even offer an option of lithium technology.
Larry

[pteck]

Originally Posted by lsbrodsky

I am sorry to dissent but I think lead-acid cells are like buggy whips. IMHO, their only advantage is cost. This 19th century technology. While I will admit that AGM's have eliminated some of the inferiorities, if you can afford an Airstream, you can afford a better electrical system. "Better" means the best available battery technology, to me, and LiFePO4 has shown itself to be that technology. Look at the junk Airstream has added to trailers today, maybe justifying price increases, but they do not even offer an option of lithium technology.
Larry

Food for thought...

The fact that Airstream has not adopted this technology should tell you something. It's not simply a matter of cost. To your point, Airstreams price point could certainly accommodate such an upgrade.

Tesla, a renowned leader in lithium batteries. You might be surprised to learn they also have 12V batteries. That are lead acid based. I don't believe they are even AGM, but regular FLAs. Even in the latest Model 3. Cost is certainly not the issue here.

Just because end users have adapted their trailers to full lithium, and are willing to live with some corner case constraints, doesn't mean they are ready for prime time.

We don't have to agree. Cost is still a big issue. But there are some real technology trades where lead acids simply are still the right solution.

I use both types of batteries in my trailer. Each has its advantages.

[rmkrum]

Even though my two Prius cars in the family are lithium batteries, and they have been proven to last over 500,000 miles in normal service, all the electronics and lights in the car run on a bog-standard 12 volt lead acid flooded battery.

The reason I know this is wife let her Prius (brand new) sit in our garage for six weeks and destroyed the 12 volt battery. Without a charged 12 volt battery, you cannot do anything with the car. Dealer replaced it under warranty, and now when either one sits, it gets a battery maintainer hooked to it.

Sometimes state of the art technology depends on antique technology.

All my fancy software-defined wizz-bang high tech solid state Ham Radio gear runs on 12 volts. I have gel cell (AGM) batteries for this purpose. Hence the Airstream being named the “Silver Ham Shack”.

[Danny Z]

Thanks all for your input! This has certainly helped a ton. I've decided to go with 2 of the Lifeline GPL-4CT batteries. One of the deciding factors for me was speaking with the owner of the company, who was very knowledgeable and helpful. I also have a nice inverter/charger that does not support lithium batteries, and upgrading that along with new batteries is a bit too much right now. Unless anyone has any final hard sells, thanks for all of your input!

[uncle_bob]

Hi

If your converter charger is over about 15 years old, it is in the "needs replacement" category. Even a newer one could be in the "that depends" region. A converter / charger for lithiums is no more expensive than a proper one for lead acid gear. The roughly $200 involved is not that big a deal compared to the price of any of these batteries.

Bob

[batman]

Originally Posted by Danny Z

Thanks all for your input! This has certainly helped a ton. I've decided to go with 2 of the Lifeline GPL-4CT batteries. One of the deciding factors for me was speaking with the owner of the company, who was very knowledgeable and helpful. I also have a nice inverter/charger that does not support lithium batteries, and upgrading that along with new batteries is a bit too much right now. Unless anyone has any final hard sells, thanks for all of your input!

Great choice. I know you will super happy with the Lifeline GPL-4CT's.
I have 4 of them currently and have not had a single issue.
I also have 2-100 watt solar panels (portable) that give me a full charge (float) almost every (sunny) day. I will be adding 2-100 watt flex panels very soon.
Best of luck with your build.

-Dennis