Your last statement I strongly disagree. Quality brand AGM’s are the only battery I’ll install for marine STARTING batteries now. If a customer insists on something else, I say have a nice day and move on. Properly size for a working charging system you can’t go wrong with AGMs and well proven. They can draw a charge somewhat harder so you can stress the system if you aren’t careful. Don’t over size the bank beyond it’s original design and you’ll be fine. I stay away from all the Chinese AGM’s because of the short life and low cranking current. VMAX, Lifeline and trojan are among the best AGM makers. I’ve also been asked to install lithiums for starting batteries but there’s four problems with that. First is most lithiums can’t handle the cranking current. Second, if they are depleted they can over tax a standard alternator. Third, the few small sized lithiums batteries that can handle the cranking current are insanely expensive. Four, I don’t trust them for starting ….yet. People + boats is not a beta tester. It’s not like you can just pull over and get out if something goes horribly wrong.As far as LA goes I’m now a fan of reasonably priced sealed wet lead acid.ie VRLA. these will not habitually vent except in extremis.
AGMs have no real place on boats. Bad idea.
Can you elaborate?AGMs have no real place on boats. Bad idea.
AGMs were designed with attributes that are hard to exploit on a boat namelyCan you elaborate?
When I got call backs within a few years with LA, sealed or not and all the AGM’s I’ve installed are still going. The results, at least to me speaks volumes. I’ll stick with results. You do you & I’ll do me. Have a nice dayAGMs were designed with attributes that are hard to exploit on a boat namely
* Very high current sustained discharge. ( not that typical on boats )
* very high recharge currents ( most boats cannot generate these ?
*not sensitive to orientation , most boats are reasonably unright
* resistant to puncture , generally people don’t fire on leisure boats !
Sadhy however their key disadvantages are all too apparent on boats
* Cost per Amp hour
* availability
* the main one PSOC sensitivity , AGMS get damaged more then any other LA technology by not being recharged on every discharge back to 100% . AGMs degrade if left to sit at less then 100% SOC or in situations where there is constant charge dischage cycling
That situation is very common on boats.
Hence AGMs have advantages that , are in the main , not exploitable on a boat whilst exhibiting disadvantage that sadly are.
Thd marketing scam here is AGMs are pushed at the Iill- informed As some sort of “ super lead acid “ battery and hence more costly. That’s not the case in boats.
Amen on PSoC use! They do work well as starting batteries though...AGMs were designed with attributes that are hard to exploit on a boat namely
* Very high current sustained discharge. ( not that typical on boats )
* very high recharge currents ( most boats cannot generate these ?
*not sensitive to orientation , most boats are reasonably unright
* resistant to puncture , generally people don’t fire on leisure boats !
Sadhy however their key disadvantages are all too apparent on boats
* Cost per Amp hour
* availability
* the main one PSOC sensitivity , AGMS get damaged more then any other LA technology by not being recharged on every discharge back to 100% . AGMs degrade if left to sit at less then 100% SOC or in situations where there is constant charge dischage cycling
That situation is very common on boats.
Hence AGMs have advantages that , are in the main , not exploitable on a boat whilst exhibiting disadvantage that sadly are.
Thd marketing scam here is AGMs are pushed at the Iill- informed As some sort of “ super lead acid “ battery and hence more costly. That’s not the case in boats.
Yes they make good staring batteries but it’s a waste of money as there’s no need for AGM In a starter battery.Amen on PSoC use! They do work well as starting batteries though...
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Starting batteries are typically under little stress as starting engines ( in good condition ) is a very light duty for a battery , while I agree AGM make a good starter it’s over,I’ll for that uses. Certainly, the typical small sailing boat engine has absolutely no need for an AGM starter , even big motorboats don’t , my last one had twin 7lYour last statement I strongly disagree. Quality brand AGM’s are the only battery I’ll install for marine STARTING batteries now. If a customer insists on something else, I say have a nice day and move on. Properly size for a working charging system you can’t go wrong with AGMs and well proven. They can draw a charge somewhat harder so you can stress the system if you aren’t careful. Don’t over size the bank beyond it’s original design and you’ll be fine. I stay away from all the Chinese AGM’s because of the short life and low cranking current. VMAX, Lifeline and trojan are among the best AGM makers. I’ve also been asked to install lithiums for starting batteries but there’s four problems with that. First is most lithiums can’t handle the cranking current. Second, if they are depleted they can over tax a standard alternator. Third, the few small sized lithiums batteries that can handle the cranking current are insanely expensive. Four, I don’t trust them for starting ….yet. People + boats is not a beta tester. It’s not like you can just pull over and get out if something goes horribly wrong.
Exactly what part of the system is damaged and why? If someone is replacing the house batteries with AGM without upgrading the charging systems or current limiting, then yes, they’re asking for it, but I’ve yet to find a starting/charging system harmed by an AGM of same AH. Unless something’s wrong or you got a fool cranking an engine that’s not going to start for other reasons and cooks a starter, or a poorly designed charging system that was on the verge, then a quality Domestic AGM will outlast the others.Starting batteries are typically under little stress as starting engines ( in good condition ) is a very light duty for a battery , while I agree AGM make a good starter it’s over,I’ll for that uses. Certainly, the typical small sailing boat engine has absolutely no need for an AGM starter , even big motorboats don’t , my last one had twin 7l
Litre 306 hp Volvos and use sealed wet VRLAs for starters, the starters gave over 10 -12 heads service life , whereas the domestics ( also wet VRLA ) were replaced approx every 5 years
I can’t count how many domestic AGM systems I’ve seen damaged from partial state of charge issues , with owners wailing that they were told AGMs where the best lead acid to buy, nothing good be further from the truth.
I’ll refine my comment ,AGMs have no place as deep discharge domestic batteries on a boat , use good branded wet VRLAs instead ( Bosch , Varta , etc ) no one around me uses AGMs
AGM domestic batteries suffering typical partial state of charge damage. AGMs need to be charged to 100% , preferably after every deep discharge. This is often difficult on boats. The result is loss of battery performance and customers getting angry at spending money and getting poor resultsExactly what part of the system is damaged and why?