Batteries

[robinbuxton]

Hi. My Service Battery on my boat needs replacing. I was going to replace it with an Absorbed Glass Mat (AGM) battery. However, my Engine Starter Battery which is still good is a standard sealed lead-acid battery (SLA). Is it ok to mix the both or will I need to change the Engine Starter Battery to AGM as well?

 

[PaulRainbow]

Hi. My Service Battery on my boat needs replacing. I was going to replace it with an Absorbed Glass Mat (AGM) battery. However, my Engine Starter Battery which is still good is a standard sealed lead-acid battery (SLA). Is it ok to mix the both or will I need to change the Engine Starter Battery to AGM as well?

You can use both, just make sure your battery charger is set to a profile that suits both.

 

[robinbuxton]

You can use both, just make sure your battery charger is set to a profile that suits both.

OK. Thank you.

 

[Koeketiene]

Hi. My Service Battery on my boat needs replacing. I was going to replace it with an Absorbed Glass Mat (AGM) battery. However, my Engine Starter Battery which is still good is a standard sealed lead-acid battery (SLA). Is it ok to mix the both or will I need to change the Engine Starter Battery to AGM as well?

Yes, you can.
Different types of batteries is not a problem as long as you don't put them in the same bank.
I have two AGM in my service battery bank and 1 SLA as starter battery.

 

[BabaYaga]

Hi. My Service Battery on my boat needs replacing. I was going to replace it with an Absorbed Glass Mat (AGM) battery. However, my Engine Starter Battery which is still good is a standard sealed lead-acid battery (SLA). Is it ok to mix the both or will I need to change the Engine Starter Battery to AGM as well?

Many modern AGM batteries allow (but do not require) charging at a higher voltage, for instance 14,7V as opposed to more normal 14,4V. This will give a shorter recharging time, which might useful sometimes. If and when you plan to take advantage of this feature it is probably not a good idea to charge an ordinary sealed wet battery in parallel, as the voltage will be too high and water cannot be added.

 

[Nina Lucia]

Hi. My Service Battery on my boat needs replacing. I was going to replace it with an Absorbed Glass Mat (AGM) battery. However, my Engine Starter Battery which is still good is a standard sealed lead-acid battery (SLA). Is it ok to mix the both or will I need to change the Engine Starter Battery to AGM as well?

We have same problem, which AGM battery you going to get?

 

[Pete7]

AGM have a number of advantages, which ones do you think you need for a house bank?

I wasn't sure whether to post this as it goes into quite some detail and might confuse more than help. However, ignore the stuff about lithium batteries and concentrate on the differences between flooded lead acid, cheap AGMs and expensive AGMs.

 

[Buck Turgidson]

AGM have a number of advantages, which ones do you think you need for a house bank?

I wasn't sure whether to post this as it goes into quite some detail and might confuse more than help. However, ignore the stuff about lithium batteries and concentrate on the differences between flooded lead acid, cheap AGMs and expensive AGMs.

The guy is paid by the Lithium manufacturer. It's a shill video pretending to be a consumer test. Ignore it.

 

[Pete7]

Which is why I said ignore the part about lithium. What is interesting is expensive AGMs don't cut it so perhaps flooded lead acid could be the better cost option.

Here is another rather surprising failure of AGM batteries in a house bank. Paul and Sheryl will be known to many as Sailing Distant Shores. The Odyssey batteries were new in mid 2018 and dead by Autumn 2020, despite having one of Nigel Calders very expensive engine generators fitted. Perhaps the 7 months Paul and Sheryl weren't on board did it for the batteries. Still disappointing, never mind the cost of 10kw of AGM if that had been you or I.

 

[Nina Lucia]

I just found this ones :

12V 130AH EXPEDITION PLUS Deep Cycle AGM LEISURE BATTERY (EXP12-130) £150.00,
12V 130AH EXPEDITION PLUS Deep Cycle AGM LEISURE BATTERY (EXP12-130) - Alpha Batteries

Made in Vietnam, maybe even same factory as Victron

Victron Energy AGM Deep Cycle Battery 12V 130Ah (M8) – BAT412121085
£289.80
Victron Energy AGM Deep Cycle Battery 12V 130Ah (M8) - BAT412121085 – Battery Megastore

Is it really possible that Victron is that much better technology AGM?

 

[jwfrary]

Leoch batteries are pretty good if your looking at cheaper AGMs.

but for the cost (double) , they won’t last significantly longer than a normal lead acid in terms of cycles, certainly not double!

so unless the other attributes are important to you like no spill or faster discharge rates (inverter use), you may be better off with traditional maintainable lead acids. Rolls or trogans

personally most things are too tall for my battery box so I’m stuck with the low profile VARTA ones. Until i come up with a cunning plan

I tend to fit exide dual agm’s when people want agm not had a premature failure yet all banks got to 400 cycles on Average before retirement, quite acceptable. I fit victron battery monitors.

lithium’s are of course longer lasting potentially , but there’s so much cost around the battery to make it safe, out of my reach!

 

[Nina Lucia]

You can use both, just make sure your battery charger is set to a profile that suits both.

Paul, How can you do that? Do you mean MPPT solar charger and shore power charger? Alternator on our Volvo 2003T is 75 Amps and I am quite sure that charging 14.4V
Is it really possible to set up charger to charge lead starter battery and separately AGM domestic bank?

 

[PaulRainbow]

Paul, How can you do that? Do you mean MPPT solar charger and shore power charger? Alternator on our Volvo 2003T is 75 Amps and I am quite sure that charging 14.4V
Is it really possible to set up charger to charge lead starter battery and separately AGM domestic bank?

You just need to make sure that whatever you use for battery charging is within acceptable parameters for both types of battery. If, for example, your mains charger charges at 14.4 volts and floats at 13.4v, if you have sealed lead acid batteries and a typical AGM battery, you're fine.

 

[Nina Lucia]

You just need to make sure that whatever you use for battery charging is within acceptable parameters for both types of battery. If, for example, your mains charger charges at 14.4 volts and floats at 13.4v, if you have sealed lead acid batteries and a typical AGM battery, you're fine.

Thank you

 

[Buck Turgidson]

Which is why I said ignore the part about lithium. What is interesting is expensive AGMs don't cut it so perhaps flooded lead acid could be the better cost option.

Here is another rather surprising failure of AGM batteries in a house bank. Paul and Sheryl will be known to many as Sailing Distant Shores. The Odyssey batteries were new in mid 2018 and dead by Autumn 2020, despite having one of Nigel Calders very expensive engine generators fitted. Perhaps the 7 months Paul and Sheryl weren't on board did it for the batteries. Still disappointing, never mind the cost of 10kw of AGM if that had been you or I.

and yet I have an Odyssey PC1800-FT as my house battery, which I fitted in June 2018 and it is brilliant. Appears to have more capacity now than when I first fitted it and I would highly recommend the brand.

 

[ithet]

I just found this ones :

12V 130AH EXPEDITION PLUS Deep Cycle AGM LEISURE BATTERY (EXP12-130) £150.00,
12V 130AH EXPEDITION PLUS Deep Cycle AGM LEISURE BATTERY (EXP12-130) - Alpha Batteries

Made in Vietnam, maybe even same factory as Victron

Victron Energy AGM Deep Cycle Battery 12V 130Ah (M8) – BAT412121085
£289.80
Victron Energy AGM Deep Cycle Battery 12V 130Ah (M8) - BAT412121085 – Battery Megastore

Is it really possible that Victron is that much better technology AGM?

Not the same, The Victron battery is quoted at 130Ah on 20a rate, the Alpha battery is 120Ah.

Many budget leisure batteries (110/130) are marked with a higher capacity by giving the 100Ah rate figure (or no rate at all). For comparison always look for a 20Ah figure.

 

[Nina Lucia]

Sorry, Alpha batteries are 130AH as well. I didn’t check 20Ah figures.

 

[Moodysailor]

I'm in the don't mix battery types camp. Definitely not in the same bank, but I wouldn't even mix if they are being fed from the same charge source (alternator, mains, wind or solar).
Different battery types absorb charge at different rates so whilst one charger maybe within the voltage range for both types the charging profiles will be slightly different for each.
It is likely that the only way you will notice is a shorter life for both batteries, which kind of defeats one of the marketed benefits for AGM.
Just one person's opinion....

 

[ithet]

Sorry, Alpha batteries are 130AH as well. I didn’t check 20Ah figures.

It's 120Ah, look at the markings on the battery shown in your link.

 

[Koeketiene]

I'm in the don't mix battery types camp. Definitely not in the same bank, but I wouldn't even mix if they are being fed from the same charge source (alternator, mains, wind or solar).
Different battery types absorb charge at different rates so whilst one charger maybe within the voltage range for both types the charging profiles will be slightly different for each.

I am far from an expert on the matter but isn't this what a DVSR is supposed to sort?