SEC AGM Batteries

L

Leonidas

Well-Known Member
Joined
7 Aug 2009
Messages
270
Location
Surrey UK and Greece.
www.leonpapazoglou.com
About to replace my 6 year old Lifeline AGM batteries unless I can somehow revive them to hold charge. Suggestions very welcome !
Looking for alternatives in the market (due to Lifeline costs)I came across the SEC AGM series of Industrial batteries .
As I understand, they are UK designed but manufactured in China industrial batteries which may also be used as service batteries for marine applications . They are advertized as deep cycle AGM technology with zero maintenance, and just the usual need to recharge . 10 year life when properly recharged and on float. They cost nearly as much as deep cycle wet batteries of equivalent capacity. They come as 12 v or 6 volts and the suppliers recommend 2x6v instead of 1x12v as they are lighter to handle (2x35kgs instead of 1x66kgs)
I would appreciate anyone's feed back on their experience of this type/make of batteries.
Also, of any comments as to the advantage or disadvantage of having 2 x 6V batteries in series instead of a single 12V ( apart from the obvious handling issue on account of weight )
Thanks
 
About to replace my 6 year old Lifeline AGM batteries unless I can somehow revive them to hold charge. Suggestions very welcome !
Click to expand...

A battery charger with a reconditioning facility

A standalone desulphator eg: http://www.courtiestown.co.uk/index.php/battery-desulphators/built-desulphators.html

EDTA: http://www.courtiestown.co.uk/index.php/battery-desulphators/edta.html There is some science behind its use.. not pure snake oil ..but probably not effective in restoring a battery already heavily sulphated
 
Last edited:
Alarmed that your AGMs lasted only 6 years. My service battery bank is a pair of 110Ah wet batts from a caravan shop which are 7 years old and were £42 each, and only now starting to show their age. I had thought of replacing with AGMs, but now perhaps I won't!
 
Leonidas said:
They are advertized as deep cycle AGM technology with zero maintenance, and just the usual need to recharge . 10 year life when properly recharged and on float.
Click to expand...

These are designed for use primarily as standby emergency batteries, kept on a constant float charge, and only used when there's a failure of mains power. Typically, they'll power emergency lighting, telecomms equipment, etc. That's not to say they won't handle frequent discharge cycles, but I think I'd want some reassurance on that point before buying.

I'm using Merlin Powerpack batteries currently, which replaced similar Delco 2000 batteries which lasted about 10 years. Not AGM, but good quality "sealed" maintenance free.
 
I'm using AGM batteries as the domestic bank - 2 x 180ah. Not sure of the manufacturer, I went to the local industrial battery specialists and told them what I wanted; they came up with 2 batteries that gave me the ah capacity I wanted that would fit in the space available. They were sold for use in golf carts, pallet lifters and the like. I charge them by means of a Sinclair mains charger when alongside, engine and solar away from the mains. They've done 4 cruising seasons thus far and sit in the bottom of the boat doing their business.

This doesn't answer the original question but as far as I'm concerned, AGM batteries do what they say on the tin: trouble free, maintainance free deep cycle batteries with a smaller footprint than comparable wet cells.
 
I bit the bullet replacing my whole battery bank,did a cost analysis of all the different battery types and came to the conclusion that flooded lead acid cheapies would be cheaper than all the exotica, even if they had to be replaced every 5 years or so.

Sensible charging, maintenance and monitoring will extend their lives.

Mind you I don't have a footprint or massive consumption issue.

3 years into the experiment so time will tell!

The starter battery I bought from a scrappy...£9...is still going strong in the same time frame.
 
My AGMs are now 8 years old. 3 x 100 Ah batteries. I use a smart charger to keep them in good shape and so far still seem fine. Is your charging regime working well? Would have expected a longer life out of AGM batts.
 
Habebty said:
My AGMs are now 8 years old. 3 x 100 Ah batteries. I use a smart charger to keep them in good shape and so far still seem fine. Is your charging regime working well? Would have expected a longer life out of AGM batts.
Click to expand...

I use a Sterling pro 40Amp charger and 1 Solara 68w panel for 1 x GpL-31 105 Ah starter and 2x GPL-40 (210 Ah each) for service.
The starter battery seems ok, but the service though appears to be full(12.7 V) it dtrops pretty quickly to 12.2 V when the fridge and Navigation lights are switched on concurrently. Load about 20 A in total.
 
Would be interesting to know if you have done an equalise charge your Lifeline AGMs. The instructions recommend it if capacity is reduced.
 
Beware - not all AGMs are the same.

As others have pointed out the Sec AGMs are probably not deep cycle designed for marine use so don't go for them just because they are cheaper.

You have had Lifelines so you know their main advantage is they charge much quicker than other batteries due to their low internal resistance, but you must have good multi-stage alternator and shorepower charging. At least 100 amps from each. They don't like it if they get charged too lightly. My Lifelines are now 8 years old and I equalize them twice a year. 15.5 volts @ 77 degC for 8 hours is Lifeline's recommendation. As far as I know they are the only AGM manufacturer who recommend equalization.

For more information download their 35 page user manual @

http://www.lifelinebatteries.com/manual.pdf

Anyone interested in comparing AGMs/Gel/wet lead acid could benefit from reading this. How many battery manufacturers have a 35 page user manual?

Also see tests on AGMs done by:

http://www.morganscloud.com/category/electrical/el-indepth-agm-battery-test/
 
sailinglegend420 said:
You have had Lifelines so you know their main advantage is they charge much quicker than other batteries due to their low internal resistance, but you must have good multi-stage alternator and shorepower charging. At least 100 amps from each...
Click to expand...
Another vote for Lifeline batteries, but I can only dream of a shorepower charger of this capacity. I have just over 600Ah, but even a 60A shorepower charger is horrendously expensive.
 
Leonidas said:
To be frank, I am not quite sure how is this done. Happy to be educated on this. Thanks
Click to expand...

See above links for the manual. My four 8D Lifelines are now 7 years old, plenty of use and when I did a capacity test at the start of the season, were pretty much as good as new. Hence, it may well be worth you borrowing or buying a charger with an equalise function and trying that before you write off the existing batteries.

IIRC, for the ambient temps we have now here in the UK, 16v is the appropriate level for the equalise cycle - there's a chart available for lifelines that shows the correct voltage for each ambient temp.
 
npf1 said:
See above links for the manual. My four 8D Lifelines are now 7 years old, plenty of use and when I did a capacity test at the start of the season, were pretty much as good as new. Hence, it may well be worth you borrowing or buying a charger with an equalise function and trying that before you write off the existing batteries. Unquote

I do have the Lifeline manual. As I mentioned i do Have a Sterling 3-stage 40A charger. Engine's alternator is 90 A. Can an equalizer that will perform at the prescribed voltage be obtained as a separate unit ??? or do I have to change the charger??
I presume, each battery should be equalized separately?
Click to expand...
 
nigelmercier said:
Another vote for Lifeline batteries, but I can only dream of a shorepower charger of this capacity. I have just over 600Ah, but even a 60A shorepower charger is horrendously expensive.
Click to expand...

Lifeline say the minimum charging current should be Capacity/5 = 600/5 = 120 amps, so you are well short of the ideal. That is the problem with AGMs - you must increase you charging systems to charge them properly, otherwise - "the cycle life of the battery may be negatively affected." Lifelines comments.

Leonidas
The batteries can all be equalized together - but you should disconnect any electrical equipment that could be affected by the high voltage. You will need a new charger with an equalize function if you are going to stay with Lifelines.
 
sailinglegend420 said:
Beware - not all AGMs are the same.

As others have pointed out the Sec AGMs are probably not deep cycle designed for marine use so don't go for them just because they are cheaper.

You have had Lifelines so you know their main advantage is they charge much quicker than other batteries due to their low internal resistance, but you must have good multi-stage alternator and shorepower charging. At least 100 amps from each. They don't like it if they get charged too lightly. My Lifelines are now 8 years old and I equalize them twice a year. 15.5 volts @ 77 degC for 8 hours is Lifeline's recommendation. As far as I know they are the only AGM manufacturer who recommend equalization.
Click to expand...

@sailinglegend
Lifeline say "Conditioning should only be done when the battery is showing symptoms of capacity loss due to etc etc"
Why do you do it twice a year, do you really find that necessary?
Agreed Lifeline are the only people "brave" enough to openly advise their users to equalise at this high voltage but behind the scenes all the manufacturers know it can be needed on occasion. We used to tell customers to do it if they were having problems and it seemed appropriate. We believed it would affect life if done more than once a year (yes this was on thick plate 10yr batteries of similar spec.)
You will lose water equalising at this voltage, there is no way round it, and all AGM batteries have very little to spare. It's a critical design factor.
How much current do you get when equalising? I doubt if it's as much as C/10 is it? That would mean the OP would have enough capacity if his Sterling charger will go to a high enough voltage - I don't know what it will give.
Even if it won't go to 15.5V, anything above 14.5V should have a good effect if the OP's problems are due to persistent undercharge rather than excessive cycling.
 
Leonidas said:
About to replace my 6 year old Lifeline AGM batteries unless I can somehow revive them to hold charge. Suggestions very welcome !
Click to expand...

Can you give a bit more detail of what sort of operating regime your batteries have please?
How often do they get discharged and how deeply, how much recharging do they get between cycles, are they ever left discharged etc? Do they always get a good recharge with the Sterling after discharging or are they ever left to just trickle up from your solar panel? What voltage does your Sterling charger go up to?
How are you judging when the batteries are fully charged? if they are showing 12.7V soon after charge that is definitely low; if 12.7 is after several hours standing with no load on, it's still a bit low. Are you confident of the accuracy of your meter?
All this information will help to indicate whether your problems are down to persistent undercharging, in which case an equalising charge (you may even need more than one) could have a good effect, or whether you have irreversible capacity loss from excessive cycling.

Note Lifeline's website says "Lifeline RV Batteries are chosen by the world's marine manufacturers as THE premium battery because 5-8 year operational lifespan is routine." and "GPL-27T (that's the 100Ah model that I assume you have) is designed for Deep Cycle Marine Applications.
The GPL-27T has an Expected Cycle Life 1,000+ cycles to 50% DOD, 500 cycles to 100% DOD" so if you have used them hard for 6 years it is entirely possible that they are simply worn out.
 
Last edited:
You must log in or register to reply here.

Share this page

Top