Marine battery compartment: don’t place lead acid and lifepo4 in the same box…
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sunshine_eggo
Happy Breffast!
Nice work covering the terminals, though. Live and learn. Expect you caught it before it's too late.
If you have no other choice, if you can keep your FLA to 13.8V and lower, they will almost never boil over at any temperature. Ventilation is recommended. A vertical barrier between them would help too.
If you have no other choice, if you can keep your FLA to 13.8V and lower, they will almost never boil over at any temperature. Ventilation is recommended. A vertical barrier between them would help too.
curiouscarbon
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thank you for allowing us to learn from this mistake.
good looking terminal covers though, seems like they prevented further damage.
looks like mainly the flat pedestal was affected
thanks
good looking terminal covers though, seems like they prevented further damage.
looks like mainly the flat pedestal was affected
thanks
The only lead acid batteries I’ll have on a boat are AGM’s as starting batteries. They should never be venting caustic fumes into the engine room, bilge or living spaces. I’ve found a radical reduction of corrosion of hardware in and around the engines after going to AGM’s. I’m afraid that the aluminum case on the Lifepo4 cells are compromised. I can’t even recommend an alkali to neutralize the acid spillage because it may do more harm than good. You probably cooked the FLA battery because of overcharging. You need to find the source of the overcharging before you replace them(hopefully with AGM’s. Vmax brand is the best I know of.
Goboatingnow
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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.
AGMs have no real place on boats. Bad idea.
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.
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pollenface
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Can you elaborate?
Goboatingnow
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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.
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 day
Amen on PSoC use! They do work well as starting batteries though...
Fighting Sulfation in AGMs - Practical Sailor
Since 1974, Practical Sailor’s independent testing has taken the guesswork out of boat and gear buying.
www.practical-sailor.com
Goboatingnow
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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...
Fighting Sulfation in AGMs - Practical Sailor
Since 1974, Practical Sailor’s independent testing has taken the guesswork out of boat and gear buying.
Goboatingnow
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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 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
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.
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Goboatingnow
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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 results
Wet acid sealed VRLA s from good origins offers the best compromise of ruggedness tolerance to bad charging practices and cost per Wh
One problem I run into frequently is old style trickle charges that slowly kill (roast) all batteries, especially AGM’s. Another thing that will definitely kill AGMs is in some newer charger is a desulfurization charge. With enough time both of those things will shorten an AGM’s life. As far as storing any lead acid, long term partial state charge is a bad thing.
The best chargers don’t have trickle. They bulk, absorb and float charge as needed and even better, just shut off and maintain. Unfortunately most of those chargers are expensive or not marine rated. The worst AGM batteries I’ve ever come across are the black shiny batteries with the white text on the sides from China and the expensive Optima brand. The best I’ve seen are the Vmax that actually got stronger at about 9 months with regular weekend use.
Then there’s always the boat owner that doesn’t realize that 12V or 24V is dead and thinks that deep cycle means a near zero volt use is ok. Probably the biggest issue is the owner.
The best chargers don’t have trickle. They bulk, absorb and float charge as needed and even better, just shut off and maintain. Unfortunately most of those chargers are expensive or not marine rated. The worst AGM batteries I’ve ever come across are the black shiny batteries with the white text on the sides from China and the expensive Optima brand. The best I’ve seen are the Vmax that actually got stronger at about 9 months with regular weekend use.
Then there’s always the boat owner that doesn’t realize that 12V or 24V is dead and thinks that deep cycle means a near zero volt use is ok. Probably the biggest issue is the owner.
It all comes down to knowledge - which most consumer don't have - want to know. They murder their batteries, regardless of chemistry.
With knowledge, AGM's perform fine. In fact, AGM was my gateway drug to LiFeP04. Once I got a handle on how to treat conventional AGM's properly, I moved up to "Pure Lead" AGM's. Oh baby - the ability to hammer them on recharge made them great for large solar paneling and limited amounts of solar insolation.
Thing is, half the time the average battery consumer doesn't even know what the words "daily cyclic" or "standby" mean and how that changes your charge profile. And as you point out, most don't know how to properly charge them to get that last 1% of charge.
AGM's are frequently just "slapped together" and blow their lids on recharge without the consumer knowing they should charge each one individually before putting them into series. How many here buy 4 drop-in LFP's, and slap THEM together without individually charging those before putting them into service? It's an indicator that it isn't a chemistry issue - rather one of knowledge.
A good source for those consumers who want the knowledge can be found on Mainesail's Marine How To site:
Always a good read.
With knowledge, AGM's perform fine. In fact, AGM was my gateway drug to LiFeP04. Once I got a handle on how to treat conventional AGM's properly, I moved up to "Pure Lead" AGM's. Oh baby - the ability to hammer them on recharge made them great for large solar paneling and limited amounts of solar insolation.
Thing is, half the time the average battery consumer doesn't even know what the words "daily cyclic" or "standby" mean and how that changes your charge profile. And as you point out, most don't know how to properly charge them to get that last 1% of charge.
AGM's are frequently just "slapped together" and blow their lids on recharge without the consumer knowing they should charge each one individually before putting them into series. How many here buy 4 drop-in LFP's, and slap THEM together without individually charging those before putting them into service? It's an indicator that it isn't a chemistry issue - rather one of knowledge.
A good source for those consumers who want the knowledge can be found on Mainesail's Marine How To site:
Electrical Archives - Marine How To
Marine How To is the premier site for DIY boaters to get in depth articles for maintenance, upgrades and insight from a professional. I sell products that I know work, because I've worked with them. I tell it like it is. No sponsors, except my readers!
marinehowto.com
Always a good read.
That’s an Excellent Read!
Found a source to “power lugs”. I test lugs and wire for the best performance (resistance/current). I found some surprising simple things to do to improve that junction that I’m going do a YouTube video on but now I’m going to do one more test lug.
Thanks for the tip!
Found a source to “power lugs”. I test lugs and wire for the best performance (resistance/current). I found some surprising simple things to do to improve that junction that I’m going do a YouTube video on but now I’m going to do one more test lug.
Thanks for the tip!
Goboatingnow
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aGMs are completely unneccessary and poor choices for boats. The PSOC issues common on boats kills AGMS faster then any other batteries. If it’s a military jet use AGM , if it’s a boat use ordinary sealed wet lead acid , this is especially true for starters where the AGM is ridiculous overkill
Not having to smell the wet cells alone is enough for me not to have them. Everything in the vicinity of the wet cells has accelerated corrosion. Air is not always circulating through boat compartments. No wind, boat at rest, no blower.
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