Lead acid vs AGM life expectancy
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They're both the same underlying technology, lead acid. A tradition battery is flooded (FLA), but an AGM has the electrolyte suspended in a glass mat, hence "absorbed glass mat", or AGM.
They both suffer from the same downsides as they're both basically the same - AGM can just be installed in any orientation since the electrolyte can't spill. There are a few minor differences with charge rates and voltages, but they're very minor, and generally, mostly irrelevant for the purpose of longevity.
Sometimes AGM's live a bit longer than FLA because of their marginally better ability to handle vibration, but in a traditional application, longevity ends up being the same in the end.
If I was replacing a battery on anything powersport at this point I'd be going with a lithium honestly - Noco makes some great drop-in replacements that are superior in almost every way, including longevity.
They both suffer from the same downsides as they're both basically the same - AGM can just be installed in any orientation since the electrolyte can't spill. There are a few minor differences with charge rates and voltages, but they're very minor, and generally, mostly irrelevant for the purpose of longevity.
Sometimes AGM's live a bit longer than FLA because of their marginally better ability to handle vibration, but in a traditional application, longevity ends up being the same in the end.
If I was replacing a battery on anything powersport at this point I'd be going with a lithium honestly - Noco makes some great drop-in replacements that are superior in almost every way, including longevity.
No they do not based on real world experience so far. But buy a quality battery though and make sure your charging system works properly and that means the voltage regulator. FLA batteries need a topping up with distilled water every year or two.
Motorcycles:
9 full years out of a Flooded Lead Acid (FLA) battery with it failing in the 10th year and that is twice now showing consistency. Both were the same brand (factory MAREG) and I now have a YUASA FLA battery installed.
7 years 4 month out of the original factory fitted YUASA AGM in my motorcycle. Replaced it with the same in 2023, so I'll see how long it lasts.
Cars: factory fitted Flooded Lead Acid Panasonic batteries 14 and 16 years in previous vehicle. I now have a FLA that is 8 years old and an AGM that is 10 years old, both of them the original factory fitted batteries. Battery tests show they are OK using my TOPDON BT 200 tester.
I stay away from lithium batteries for various reasons.
I consistently get 6-7 years out of the original batteries in my new bikes provided I keep a Battery Tender on it over the winter. They have always been made in Japan Yuasa’s. The replacement Yuasa batteries you get here are made in USA and I only seem to get about 4 years out of those. As for Lithium batteries, I’ve never used those. I thought the charging process was significantly different, at least they are on RV batteries. Does anybody know if the drop in lithium batteries will work on a lead acid/AGM charging system?
Yes BUT.
The charging system voltage has to deliver 14.4 volts to charge them properly. Most modern charging systems designed for sealed maintenance-free batteries will do that, but some old skool systems designed for the old batteries with fill caps do not. A charging voltage in the 13s will kill a LiFePo battery. Found that out the hard way.
Also, LiFePo batteries are not suitable for below freezing temperatures. They can be stored below freezing, and discharged slowly, but not charged. For most motorcycle applications, this is not really a problem
It depends where you live as two things kill batteries: heat and vibration and of course owner neglect. Now there is not much you can do to a sealed battery other than maintaining its charge. And that is why I much prefer FLA batteries because I can add distilled water to them and overcharge them for cell balancing.
And a Flooded Lead Acid (FLA) battery and those are the ones with filling caps be it that they are flush or stick out charge at 14.4V at 77F (25C) if my memory from the battery lab serves me correctly.
A so-called sealed (and they are not really sealed for safety reasons) fall under VRLA type (Valve Regulated Leat Acid) battery and the AGM and GEL have different charging voltages.
Note also from the charts, that as the temperature rises, the charge and float voltages decrease and vise versa.
On one of my motorcycles that came factory fitted with a GEL cell (BMW) it would chrage at 14.0V to 14.2V MAX but closer to 14.0V and 14.1V in the temperatures I was riding at 15C+.
On my latest motorcycle (BMW), I usually see 14.1V to 14.3V and that is a bit low for the factory fitted AGM it came with.
When I say "low", it isn't a feeling as I worked with batteries in a government lab. It is why my batteries last and the ones in cars lasted 16 and 14 years for a conventional FLA battery.
Same here. I see all these promises from a very popular Lithium Battery vendor (no name mentioned) that I call BS to. The owner is a salesman and from what I have seen has very little technical background and repeats useless info like a parrot.
For example, 2X to 3X the battery life. Really? Is he going to tell me I will get 18 to 27 years from a motorcycle battery or 28 to 48 years from a car battery. Yeah right.
Then there is that "more cranking amps" he advertizes. What for when my stock batteries start my motorcycle for 9 years until they reach their end of life for a low-tech conventional battery at a fraction of the cost. I just replace it as batteries are a consumable.
And lets not get into that H7 80Ah I will need for my car one day. US$1350 (CA$1890) vs about CA$250 from Walmart or Costco. The original factory fitted AGM in my car just passed the 10 year mark and it started right up last week.
But I do like a Lithium in my mobile phone, tablet and digital camera. Lithiums have great energy density and take charges well especially if they are single cells where you can control the charging.
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It's based on charge cycles, and yes, newer LifePo4 cells are reaching astounding numbers of battery cycles while still maintaining a huge majority of their capacities. There are millions of these batteries out there now in energy storage/solar/off grid applications, some which are cycled with huge SOC swings multiple times a day every day, and have been for years, and are still healthy.
A motorcycle in comparison to something like a energy storage bank at a EV fast charger for one example is childsplay comparatively, so yeah, they will last a very, very long time.
Sorry no. I have lithium batteries and their capacity is nowhere near of what they were 5 years ago when they were new. And these are single cell batteries.
So 48 years or even half of that, forget it. All they have to do is change their claims. Of course anyone is free to choose how they spend their money foolishly.
I've had Lithium batteries on close to half the bikes I've owned in the last 5 years.
IME, the life expectancy is about the same as AGM, brand is a good indicator of quality and life - same as with anything else. Had a crappy lithium give up the ghost 3.5 seasons in - regular maintenance with a lithium-specific tender. Have had AGMs last as long as 8 years (car battery).
The only real tangible benefits of Lithium over AGM is:
1) Greatly reduced weight and size
2) Slow discharge rate
3) Battery Management System will prevent damage from deep discharge or over-charging
Disadvantages:
1) There is no warning when a lithium will fail. One second you're getting 13.3v, the next you're well below 12v. With Lead Acid/AGM, the battery's health will decline over a longer period of time. Gives you time to swap the battery out when you notice it's not cranking as strong as it once was.
2) Battery needs to be warmed up in extremely cold weather - they recommend turning on your headlights for a few seconds before cranking. However, I've started my lithium-powered bikes in -10C weather regularly with no waiting, never a problem. I think they may be talking about temps around -40C?
3) More expensive
IME, the life expectancy is about the same as AGM, brand is a good indicator of quality and life - same as with anything else. Had a crappy lithium give up the ghost 3.5 seasons in - regular maintenance with a lithium-specific tender. Have had AGMs last as long as 8 years (car battery).
The only real tangible benefits of Lithium over AGM is:
1) Greatly reduced weight and size
2) Slow discharge rate
3) Battery Management System will prevent damage from deep discharge or over-charging
Disadvantages:
1) There is no warning when a lithium will fail. One second you're getting 13.3v, the next you're well below 12v. With Lead Acid/AGM, the battery's health will decline over a longer period of time. Gives you time to swap the battery out when you notice it's not cranking as strong as it once was.
2) Battery needs to be warmed up in extremely cold weather - they recommend turning on your headlights for a few seconds before cranking. However, I've started my lithium-powered bikes in -10C weather regularly with no waiting, never a problem. I think they may be talking about temps around -40C?
3) More expensive
Li ≠ LifePo4
Chemistry matters. The batteries that are in your phone are pouch style lithium and do age more rapidly than lithium iron phosphate batteries, but the smaller the battery the more rapidly the tend to age as smaller batteries in things like electronics are usually exposed to much deeper and more regular cycles (ie cellphone battery) vs a larger battery that may only see a 20-50% SOC swing, and they are air cooled and subject to major temperature swings, and heat is the mortal enemy of lithium longevity which is why EV’s liquid cool their packs. Also, lithium batteries left at 100% SOC for long periods of time is also not healthy, ie a laptop that is seldom unplugged. A lot of the most common cells like 18650’s are also regular lithium but cylinder style vs pouch.
There’s a reason you are now seeing battery configuration options in most phones and laptops where you can set a top charge SOC for times when you don’t need the entire battery and don’t want it to sit at 100% for long periods. This is commonplace in EV’s as well.
Lifepo4 on the other hand is a very different beast that is not only far more tolerant to large swings without significant capacity loss, but builds heat at a lower rate, isn’t subject to thermal runaway, and has a much higher tolerance for abuse in many ways.
Ultimately a lithium in many ways is only as good as how it’s used based on its chemistry, and it’s BMS, and often, how that BMS is programmed - conservative vs “squeeze every last watt of power in and out all the time”.
I scratch build lithium battery banks for different applications on the side, so I know a few things about them, including chemistries and BMS programming. This is one I built for myself a few years ago that’s currently in our camper for example:
1) I am not worried about an extra 5 pounds in weight on my motorcycle or an extra 26 pounds in my car.
2) As long as the battery is disconnected or has absolutely no drain on it when it is connected.
Lead acid has a self discharge rate of up to 15% per month l, even completely disconnected from any loads.
Lithium tops out at 3% per month and is generally much less. I left the lithium pack above in our camper all winter at 70% SOC with the BMS in sleep mode and when I powered it up again a few weeks ago it was only down to 69%. A regular lead acid would have lost more than 50% of its SOC over that time and would’ve probably frozen and been irreparably damaged which is why it’s important to put lead acid batteries on tenders for periods of storage.
Yes I know there are different chemisties of Lithium batteries.
And in all cases of battery types, the proper type of charging helps long life. It is why my batteries last far longer than anyone elses.
And yes, I also know about the charge level when storing, but in my cases where they are used, they get fully charged and discharged, I am not worriied about the storage charge.
And in the end, in the real world, I still go with an FLA and then an AGM because they are drastically cheaper and last longer.
Yeah so. That is why I put it on a maintainer if it is stored.
My lead acid batteries also last 16 years.
You are trying to educate the wrong person on batteries.
Pricing has come down so much for deep cycle applications lithium is a no brainer almost the same price as lead acid
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In my 50+ years, based on real world experience.
If I got 14 and 16 years from a conventional flooded lead acid battery, why would I pay more for a lithium or an AGM battery even if it got that many years out of them.
I could tell you my secrets which are top secret, but then I'd have to shoot you.
The trick is, never listen to someone on the web that is a vendor who has a vested interest...like battery vendors. That is like going into a GM dealership and asking them if a Ford is a great car.
Really and will I get 9 full years out of a motorcycle battery or 16 years out of a car battery.
From what I have read on various forums, many are not getting a long life out of a lithium.
I have 600amp of lithium in the RV lead acid batteries are terrible in this application they only last 2 years max and lithium are good for at least 10 years with twice the usable amps. No comparison I can be off grid for over a week and use the ac daily.
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You might want to rewrite that because I am uncertain of what you are saying.
Are you saying your lead acid batteries in your RV only last 2 years. Well of course as those batteries were never meant to go into a deep discharge. Those applications work best with batteries designed for that purpose.
We are talking SLI batteries used in motorcycles and cars here.
