Several years back, when I first heard of Full River AGM batteries, I was intrigued, as they were supposedly Rolls Surrett's AGM's, just built in China, and Roll Surrette, in the deep cycle, flooded Lead acid battery world, are basically top dog.
I'm on my Second Northstar. TPPL AGM
The first lasted 6 years and ~1200 deep cycles. with at least 200 of those deep cycles to well below the 50% state of charge boogeyman.
By far the best lead acid battery I've ever owned.
I am not sure its replacement, bought in 2018, the group Northstar group 31, 1150CCA 103AH that I am cycling now, is as good as the 1200 deep cycle 2012 era group 27, 930CCA 90 AH, was.
Time will tell, but in many respects, it seems equal, or slightly less.
The only way to truly and accurately compare is not, x amount of time, but amount of work the battery actually performed while it lasted throughout whatever discharge/ recharge regiment it was subjected to in its lifespan.
This means the tools, interest and many observations of amperage acceptance and voltage retention during X amount of loads for X amount of time, in the charge and discharge schedule, and disregarding the ' I bought it therefore it must be best' mentality.
Tell me that I'm pretty........
I can report that those cycling Full river NON TPPL AGMs, claim pretty good lifespans from them, but this can be misleading, as those who can actually accurately report good cycle life, and actually make the effort to do so, also often know that returning AGMS to full, after many partial state of charge cycles, can take ridiculous amounts of time, when held at higher voltages. Such people who report good lifespans in deep cycle service, also have the charging equipment that allows/ can allow for these extended absorption voltage stages that are often neutered by common garage 'smart' charger algorithms, which were never intended to keep a deeply cycling battery happy, long term.
When cycling AGMS, regularly receive the true full charge, they often live good long lives, and when they don't, they often don't.
Another factor with Deeply cycled AGM's, is that low and slow 'trickle charges', from a well depleted state, tickle them to a premature demise. They need the occassional high amp recharge from a well depleted state, and then held at the correct absorption voltage for as long as it takes for amperage to taper to very low levels, to retain their capacity and CCA.
Well depleted means they can accept higher amperage for longer. Heats things up, dissolves sulfation, forces electrolyte migration through the plates/ grids.
Stretch their lungs, a little exercise being a good thing here and there, just don't drain them slowly to below 10.5v thinking a 10 amp charger is doing them anything good. Take them to 11.9v or less, and them immediately hit them with no less than 40 amps per 100Ah of capacity. My 103Ah northstar has no issues accepting 134 amps when 55 to 60 amp hours from full, even into its third year and several hundred deep cycles.
Good luck finding a 'smart charger' with more than 25 amps available.
Regular Joe Q Key Turner, who might only see a voltmeter's readings once and a while, and never ever an ammeter, has no Idea, just a useless opinion, full of sound and fury, and fan boy opinions, signifying only brand loyalty, and insecurity, coupled with inexperience, to share.
If the Full river fill throttle AGMS are similar weight and CCA and capacity specs as Northstar and Odyssey in the came BCI case size, and the same price, well, go for Northstar or Odyssey.
If FUll river full throttles TPPL AGM's are significantly cheaper, well, Northstar an Odyssey, are Made in USA.
That alone, should be rewarded, and encouraged.
AGMS are finicky princesses, they are NOT immune to abuse, they are not super Lead acid batteries, they often disappoint.
They are liable to pack up all their toys, and stomp off home, if treated like the basic commoner flooded lead acid that cost 50% less.
Their advantages in potential lifespan require that they be return to true full charge often, but especially when they are cycled deeper, intentionally or not. A modern vehicle parked for 3 weeks can be considered a deep cycle, and an abusive one at that, as it is more damaging to be slowly depleted to 50% or less, over three weeks, than it is to be depleted to 30% state of charge quickly, but then instantly recharged to full or nearly so.
If AGM's are treated poorly, they are not worth their premium.
If they are coddled, they can yield impressive performance and lifespans, and not being located in an engine compartment seems to be a huge factor with AGM lifespans, regardless of the vehicle's allowed voltages, and are much more finicky to charging voltages/ duirations of those charging voltages, to a mugh higher degree than flooded lead acid batteries.
if they are ignored and the vehicle sits undriven for extended periods without use, and has a MPG based voltage regulator algorithm, they can go belly up in 6 months.
The high end high $$ AGMS are no exception to this, and the low $$ AGMS are built to be profitable, enticing those who believe an AGM is always an 'upgrade', and they really need an upgraded 'something' at this point in their life.
What does it weigh?
More lead/ weight, is a good thing with lead acid batteries, but even better is the voltage regulator in the charging source, that brings the discharged battery to the correct voltage for the right amount of time to be considered full, or as close to this ideal as is possible,
This time is highly variable, depending on temperature, and battery health, and also the amount of time since the last true full charge was performed.
The cheapest lead acid battery kept close to fully charged, with however much additional effort that requires, beyond what the vehicles charging system can or tries to provide in the time the vehicle is actually on and driven, will greatly outlive the most expensive battery always kept at 85% average state of charge
So basically,
Odyssey/Northstar TPPL AGM, Made in USA,
Full river full throttle, made in China.
Even if it is equal in potential performance.....
Is this where you need to save a few bucks?
www.fullriverbattery.com
www.northstarbattery.com
www.odysseybatteries.com
The Odyssey claims to weigh the most, yet also has the least capacity at 100 AH..
Of the three, It would be my choice, and I use a good % of their capacity, often.
www.remybattery.com
