Tired of dead batteries....

[mcgyver]

I have 2 marine batteries hooked to a perko 2 way switch, run out to fishing on #2 for the main motor then switch to #1 for the trolling motor/downriggers ect. Should i run out with the perko to "all" and will that charge both?(run is 10-20 minutes)Trolling motor is set to charge #1 main motor charges #2. Can i install a voltmeter to detect the "condition" of both batteries before i leave? Would it typically read above 14 volts if the battery was fully charged? I'm tired of arriving out to fishing and finding that the #1 battery is under charged to start the 9.9 yamaha and the downriggers. i need a foolproof system set up. Suggestions...... last trip out with the family switched to #1 and found it was dead...didn't like the idea of being out with only 1 battery charged!!!!!!

 

[bruceb58]

Re: Tired of dead batteries....

10-20 minutes is not going to charge your batteries hardly at all. They need to be topped off before you start your day with some sort of battery charger. You need to keep them fully charged when you aren't using your boat. Batteries that are stored discharged will fail early in their life.

 

[Boatist]

Re: Tired of dead batteries....

I agree with Bruce.
Never start a trip without fully charged batteries. For 12 volt Lead Acid Battery that is 12.6 volts.

Charge both batteries while under way. Use a ACR or VSR or battery isolator what ever works best for you.

Before you leave the boat at the end of the trip make sure all batteries are fully charged. Use a Automatic or smart charger, or on board charger but some way to fully charge batteries at the end of the trip.

For me I use a 10 amp fully automatic charger at home hooked to a plug on the bow of the boat and charge both batteries thru a battery isolator. I can also charge while going down the road on the trailer form my turcks 100 amp alternator. This I use a 8 guage wire and charge from the same plug on the bow of the boat. I only done this a few times. Usually only charge this way when have been night fishing and had short 20 minute run back to the trailer then head home.

Most times I make sure batteries are charged day before a trip. Then on the trip any time my I/O is running batteries charge automaticly. When I get home first thing I do is plug in and turn on my battery charger. Then unload the boat of all the gear and garbage and fish. Clean the fish and cover the boat then go and check the charger to see if battery if fully charged. In my case usually fully charged in less than 10 minutes but I do not have electric trolling motor or a 100 watt stereo that has discharged the batteries.

As Bruce said the longer a battery is discharged the shorter it life will be.
I believe that most batteries do not die on their own.
I believe they are killed by their owner not chargin them properly.
Even if the boat has not been used at all batteries should be charged every 2 month in cold weather and every month in hot weather.

 

[Silvertip]

Re: Tired of dead batteries....

The long and short story with battery switches is this:

Whatever position you have the switch set for is the battery that is powering everything and it is the battery that is being charged. So when set to BOTH, both batteries are powering everything and both are being charged. HOWEVER - the output rating (amps) of the engine alternator determiines the "rate" at which the batteries are charged. As was pointed out, a 10 - 20 minute run will provide almost no significant charge to a nearly dead battery. Lastly -- NO! A fully charged battery does not measure 14 volts. It measures 12.6 volts. 14 volts is the typical charging voltage when under way.

 

[lncoop]

Re: Tired of dead batteries....

You don't mention your charging method for while the boat is stowed, so I'll assume you don't have an on board charger. If that's the case you might try installing one. There is no foolproof system setup, but they really make a boater's life easier and make your batteries last longer. As long as you remember to plug it back in when you get home from the water you'll never have dead batteries. Very good ones can be had for under $200.

 

[mikphilips]

Re: Tired of dead batteries....

McGyver,
After spending hours reading the posts on this forum related to batteries and scouring the internet for info on wiring and devices, I have come to the following findings:

1. Install new / or prove your batteries are good
(have auto parts store load test your batteries, replace with best marine
batts you can afford if they are weak, and make sure your batt types
match the use; dedicated starting vs deep cycle for trolling and
electronics, etc)

2. Connect your engine's alternator feed directly to the starting battery.
If you have the cash and the room, use two batteries. One dedicated
for starting your engine, the other for running all other 12v devices
(VHF, stereo, sounder, etc.)

3. Connect your engine's alternator feed to the trolling and/or electronics
battery through an integrator (Newmar BI-100 or sim device, wired
between your starting battery and your trolling battery will
automatically connect the batts together when it senses a
charging voltage from alt, it will also disconnect the batts from
each other when there is no charging voltage present / when
you are discharging the batteries during the use of electronics, this will
keep your starting battery from being discharged while stopped).

4. Install a smart onboard charger, wired to each battery separately
to use 110v power at home to recharge each battery according to
its unique need. Install an simple on-off marine battery switch
(Perko, Guest, etc) on the hot wire that feeds the integrator.
Switch it OFF just before charging batts at home with onboard charger.
Switch it back on after charging before using the boat.
If you place printed reminder at plug on boat where you power up
the onboard charger, you will likely remember. If you forget,
the onboard smart charger charges each battery the same or
the engine alt will not charge the trolling battery. Many say this is
not a great loss, but a little is a lot if it takes you to that last spot
and the fish are biting.

5. Install small LCD voltmeters to each battery so you can monitor
the voltage in / or going to each battery. They are small and cheap and
let you see exactly what's going on for each battery. By using the chart
below, you can see if each of the batteries is receiving a charge
and / or what degree of charge each batt is holding:

VOLTAGE % CHARGED STATUS
>14.6v Charging Overcharging; problem w/ charger
13.7-14.5v Charging Charging correctly
12.6v 100% charged Batt & charger is in good shape
12.4v 75% charged Time to lose 25% of charge is approx
1/2 time to lose 50% of charge (12.2v)
12.2v 50% charged Battery may not start engine
12.0v 25% charged Battery will not start engine
11.8v 0% charged Battery is 'dead'

6. Get in the habit of checking the voltmeters while using the boat.
Starting batt should not use / drop voltage when engine is stopped,
if isolated from electronics battery (house battery) by integrator.

7. If you have leaky boat and bilge pumps run / cycle on while stopped,
wire bilge pumps to house battery so they don't kill your starting battery.

8. Cover the tops of your batteries (if they are not in a fully enclosing
battery box) to prevent accidental shorting from gear stored near
your batteries.

9. Carry a 12v 'Start Stick' portable battery booster device to start your
engine and get home if problems arise. Modern two-stroke engines will
run without a battery after they are started.

10. Learn how to use the pull starter rope if your engine has one.
Its the McGyver way to save the day!

I suspect others will suggest refinements or overhauls to the previous points,
but they have worked well for me.
MikPhilips