Santiago
Ultra Nomad
Posts: 3499
Registered: 8-27-2003
Member Is Offline
|
|
Best boat battery for occational use
18' aluminum boat with a 115hp merc. Has two group 24 marine batteries and a Perko switch to alternate between them. I normally switch from one
battery to the other near the end of the day so the ride home charges it; then use that battery for the next days fishing.
1. Engine manual says to never switch the batteries, using the Perko selector switch, while the engine is running as it may damage the charging
system. Anyone know if this is really true or just a CYA? It also says to never have both batteries connected at the same time. Again, is this just a
CYA or a real concern?
2. I will use this boat 3 or 4 times a year for a few days in a row; then it will sit in Baja, off grid, for a 2 or 3 months with the selector switch
to 'Off'. Given this use, is lead acid better than AGM? Last year I got a couple of group 24 AGMs from Cabellas but I feel I get better results from
a Sears DieHard marine-starting. One of the AGMs had failed already.
3. Regardless of the type, should I hook up an extra 15 watt solar panel to a trickle charger while I'm gone?
Thanks
|
|
|
larryC
Super Nomad
Posts: 1482
Registered: 8-11-2008
Location: BoLA
Member Is Offline
|
|
Costco batteries are now a 42 month free replacement so if one or both of your batteries goes bad in that time period they will replace it. So I put 2
of them in my boat. I'm pretty sure at least one of them will go bad bad in that time period.
Don't know about harming the charging system by switching the battery switch. Maybe it could if you switched from one battery to the other by going
through the "off" position on the switch.
[Edited on 5-8-2016 by larryC]
Off grid, 12-190 watt evergreen solar panels on solar trackers, 2-3648 stacked Outback inverters, 610ah LiFePo4 48v battery bank, FM 60 and MX60
Outback charge controllers, X-240 Outback transformer for 240v from inverters, 6500 watt Kubota diesel generator.
|
|
|
SFandH
Elite Nomad
Posts: 6924
Registered: 8-5-2011
Member Is Offline
|
|
I take my boat batteries home with me and keep them stored in heavy plastic battery boxes and charged up with a trickle charger, monthly more or
less.
[Edited on 5-8-2016 by SFandH]
|
|
|
willardguy
Elite Nomad
Posts: 6451
Registered: 9-19-2009
Member Is Offline
|
|
which ever you choose I'd cart em home after each trip, keep em charged in the garage out of the heat. we do this with our solar house batteries.
its workin for us 
and check with captKW about the switch 
[Edited on 5-8-2016 by willardguy]
|
|
|
Santiago
Ultra Nomad
Posts: 3499
Registered: 8-27-2003
Member Is Offline
|
|
Quote: Originally posted by larryC  | Costco batteries are now a 42 month free replacement so if one or both of your batteries goes bad in that time period they will replace it. So I put 2
of them in my boat. I'm pretty sure at least one of them will go bad bad in that time period.
Don't know about harming the charging system by switching the battery switch. Maybe it could if you switched from one battery to the other by going
through the "off" position on the switch.
[Edited on 5-8-2016 by larryC] |
I think you are correct about the 'Off". The Perko is a 90 degree switch, not a 360, and the off is at one end, and they are 'make-before-break' so I
think should be no problem.
![31620_L1[1].jpg - 39kB](https://forums.bajanomad.com/files.php?pid=1033994&aid=33820 "31620_L1[1].jpg - 39kB")
|
|
|
Santiago
Ultra Nomad
Posts: 3499
Registered: 8-27-2003
Member Is Offline
|
|
| Quote: Originally posted by willardguy | which ever you choose I'd cart em home after each trip, keep em charged in the garage out of the heat. we do this with our solar house batteries.
its workin for us
and check with captKW about the switch
[Edited on 5-8-2016 by willardguy] |
I've thought of that but they are a real pain to get out of the boat and the older I get the heavier the darn things get. Somehow it seems to me that
with 400 watts of solar panels 20' away from the boat, I ought to be able figure out a charging system. Good point on the heat though.
|
|
|
TMW
Select Nomad
Posts: 10659
Registered: 9-1-2003
Location: Bakersfield, CA
Member Is Offline
|
|
When you switch between batteries with the engine running there is the possibility of causing spikes that could damage the charging system. You could
do it a hundred times without a problem then one more time and bam it goes.
It could be they are concerned about the amount of current in charging two batteries verse one as to why they don't want them both connected at the
same time.
Yes, I think it is a CYA thing for them.
|
|
|
Hook
Elite Nomad
Posts: 9006
Registered: 3-13-2004
Location: Sonora
Member Is Offline
Mood: Inquisitive
|
|
What kind of batteries are you using at your casa? If you utilize that charging system, you will be dependent on the type of battery the charge
controller is set for. Get the same type.
But if you want to use that charging system, wont you still have to remove the batt from the boat? I am assuming you have no enclosed, lockable garage
where you could run some type of leads to the battery in the boat, itself, without compromising the security of your living abode.
If using a separate 15w charger, that would probably have to be in direct sun for 2-4 hours/day, to counteract the natural tendency of batteries to
discharge. Is that possible to do? Or are you talking about a separate 15w charger that could be powered by your solar array?
I've pretty much given up on buying batteries in the US and bringing them down to Mexico. Yeah, there is better battery technology up there than LTH,
Gohner, etc., but the heat just kills batteries down here, well before the warranty. Then, there is the hassle of returning it to the States and
bringing the replacements down. I am just paying for the LTHs (cheaper than most batts in the States) and living with the shorter lifespan. Return is
within a 20 minute drive for me. I just bought my first set of 105a/6v LTH batteries last week, for the "house" bank on my boat. But it's never in the
water more than a couple weeks (w/o shore power, BTW) and then it's in an enclosed garage on a trickle charger. We'll see how long these last. My
Kirkland 6v golf cart batteries did last 6 years; not bad at all. My "starter" LTH group 31 has also made it 6 years. It should be going soon.
I realize that BOLA has limited options for this buy-and-return-in-Mexico scenario.
I'd go lead-acid, flooded cell and let's see what people say about those filler caps that supposedly prevent moisture loss while charging. I have seen
them, but dont know how well/long they work. With your long periods away, electrolyte loss would seem like your biggest worry.
I checked to see if there is any kind of battery lifting tool that reduces this PITA but all I see are one-handed options. Still so much weight for
us, as we age.
Isnt there an enterprising young Mexican running around Gecko's who will do the lifting, whenever you need it, for a few pesos. THAT'S the best
lifting tool, I see.
|
|
|
woody with a view
PITA Nomad
Posts: 15937
Registered: 11-8-2004
Location: Looking at the Coronado Islands
Member Is Offline
Mood: Everchangin'
|
|
seems like AGMs negate the off-gassing, run electrolyte dry problems. if it was me (i'm no expert, but i did stay at a holiday inn express last week!)
i'd put some AGMs in the boat. the day you get back to Baja put them on a charger, generator or your casa solar for a few hours.
|
|
|
landyacht318
Nomad
Posts: 247
Registered: 7-28-2007
Member Is Offline
|
|
Never turn Perko 1/2/both/off switch to OFF with engine running. Doing so could easily blow the diodes in the alternator.
All lead acid batteries ideally want to be 100% recharged and stay 100% charged their whole lifespans.
Anything less than 100% is detrimental to their lifespans.
it takes TIME at absorption voltage to fully charge a lead acid battery. While a high amp charging source can get a depleted battery to 80% charged
relatively quickly, from 80 to 1005 charged will take about 4 hours, no matter how powerful the charging source is, and this 4 hours is when the
battery is held at its ideal absorption voltage for its temperature, which is ususally ~14.4 to 14.8v at 77F.
I know people like to believe an alternator is a near instant magical battery charger, but they are far from. 80 to 100% charged takes 3.5 to 4 hours
and takes even longer when the battery is less than healthy or has seen many discharges without a full 100% recharge.
So it is likely your previous batteries were stored barely above 80% charged and then self discharged and lost capacity quickly while you were away.
AGMS are NOT super batteries that their price indicates. They actually require the full 100% recharge more often than their flooded counterparts/ all
factorss being equal.
AGMS also occassionally need a higher amp recharge from their most depleted state. you can tickle AGMS to death using grandpa's 'trickle charge
everything, always' mentality on AGMS. Cheap AGMS should not be fed more than 30AH per 100AH of capacity. Higher $$ AGMS like Lifeline, Northstar
and Odyssey have no upper limits on charging amps. Odysseys says no les than 40 amps per 100AH of capacuty when deeply cycled.
Getting maximum longevity from lead acid batteries can be taken to extremes.
Acceptable lifespans can be achieved simply by knowing that 100% charged is very important, and that 100% charged from 50% charged basically cannot be
accomplished in less than 5.5 hours, on flooded or AGM, no matter how powerful the charging source might be.
http://www.pbase.com/mainecruising/effect_of_charge_rate_on_...
Proper absorption voltage is dependent on battery temperature and different among different battery brands.
lifeline Northstar and ODyssey all have extremely low self discharge rates, in the 2 to 3% per month range at 75f. Flooded batteries when still
healthy can discharge 15% per month at 75f average.
Keep the batteries as cool as possible. Ensure a full charge before removing all loads on an AGM and it will be good in 6 months or more.
A 15 watt solar panel still requires a charge controller, and the controller;s float voltage needs to match the battery manufacturer spece. lifeline
13.2 to 13.4v at 77F, Northstar and Odyssey are 13.6v at 77f.
I am cycling the pee out of a Northstar group 27. I am at anbut 300 deep cycles, to 60% or below and another 200 cycles 85% or above, in 2.5 years.
It is still performing Awesome, but it requires that high amp recharge at least every 5 to 6 deep cycles, from 50%, and it requires the 100% recharge
almost every recharge.
Otherwise performance tanks and the battery voltage drops farther faster during discharge, and time to full can increase to 10 to 12 hours when held
at absorption voltage.
Northstar batteries are sold as X2 power at batteries plus and they add another year to the 4 year warranty, can get Northstar batteries at American
battery in Escondido.
Northstar and Odyssey have very high CCA figures and are still able to handle deep cycles. LIfeline batteries have thicker plates and are more
resilient in deep cycle duty, but do not have the super high CCA figures on desires in engine starting. lifeline does make starting batteries too.
Lifeline is pretty much the Top Dog AGM, in my opinion.
|
|
|
Santiago
Ultra Nomad
Posts: 3499
Registered: 8-27-2003
Member Is Offline
|
|
| Quote: Originally posted by landyacht318 | Never turn Perko 1/2/both/off switch to OFF with engine running. Doing so could easily blow the diodes in the alternator.
So it is likely your previous batteries were stored barely above 80% charged and then self discharged and lost capacity quickly while you were away.
|
In your view, is it OK to go from 1 to 2 with the engine running? I understand the 'off' issue as there are no isolators on this boat.
|
|
|
Hook
Elite Nomad
Posts: 9006
Registered: 3-13-2004
Location: Sonora
Member Is Offline
Mood: Inquisitive
|
|
I switch batteries while running all the time with my Volvo diesel. And it has an alternator where the diodes are susceptible to this. I've never had
a problem with it.
I just never shut off a diesel engine on the water. Even drifting, it's running. If an engine is working and running, why stop it? Too afraid of an
electrical issue that may prevent it from starting again, while I am dozens of miles, offshore.
I love the smell of diesel in the morning.............smells like, FISH ON!
|
|
|
landyacht318
Nomad
Posts: 247
Registered: 7-28-2007
Member Is Offline
|
|
Switching batteries or going one to both to 2 is fine as long as the switch is 'make before break' meaning it combines the circuits before releasing
the previous battery choice.
Not that I have searched for them, but I do not know of any break before make switched, they are all make before break
When underway, I'd recommend choosing both as it simply takes so long to fully charge a battery. Just be sure to turn switch through both, and not
off if the switch allows such an option, Such as the blue seas 6007m series
|
|
|
![[*]](images/xmbforum/default_icon.gif){kind=icon}
