background image

Important Charging Information

Any of the following actions will void the warranty!

Exposure of battery to gasoline or diesel fuel.

Removal of the battery’s top cover.

Removing or destroying the battery’s shipping date code.

Long Time Storage

If you are going to store your boat for longer than 60 days you 

will need to take the following steps to prevent long term dam-

age to the SEA27.

1. Disconnect the battery from any power draining devices.

2. Do not leave a trickle charger on the battery.

 This will 

overcharge the battery. Use an AGM smart charger.

3. If you have components that need to stay powered during 

storage, ie: car alarm system, you may use a battery tender 

device. They have a regulated output that will monitor battery 

voltage closely and keep the battery at peak voltage. Choose a 

tender that has the ability to reduce charge to .05 amps (five 

hundredths of an amp, not half an amp). 

4. Do not store battery in a discharge state. 

Battery Testing

Testing your SEA27 to determine its functional condition can 

be done in two ways. The first is to test the open circuit 

voltage of the battery to determine the state of charge 

with a voltmeter.  Testing Open Circuit Voltage means 

testing the battery’s voltage with nothing connected to the 

battery (disconnect one terminal).   

Consult the chart below to compare your readings:

Having the proper 

battery or amount of batteries for the system to be 

powered is extremely important to the life of the battery.  

When planning your power delivery system make sure you 

have the right amount of battery power so as to not 

discharge the battery too deeply during normal operation. 

Even though the Stinger batteries have the best deep 

cycling ability in the market, the deeper the battery is 

cycled the shorter the life expectancy will be. This is evident 

Typical Stinger SEA27 Cycling Ability 

vs. Depth of Discharge

Depth of Discharge

100%

50%

30%

10%

Typical Life Cycles

400

800

1450

4000

If you have any questions, please discuss battery selection 

with your Stinger dealer or contact technical support prior to 

installation.

State of Charge vs. Open Circuit Voltage

State of Charge

100%

75%

50%

25%

0%

Open Circuit Voltage

12.85 volts

12.5 volts

12.2 volts

11.9 volts

11.6 volts

Proper Battery Selection

The second way to test the battery is by using a load tester 

(usually available at your Stinger dealer or most auto service 

centers).  A load test is performed on batteries that are suspect 

of having reduced output capacity. For example a battery’s open 

circuit voltage tests good but the battery is unable to support a 

load.

You have purchased the most technologically advanced 

battery available for the extreme demands of the marine 

environment. When properly installed and maintained the 

SEA27 will provide years of trouble free service. Some of the 

advantages you will gain by using the SEA27 are:

- Greater amounts of power available on demand for your

audio system, accessories and starting power.

- Freedom to mount in any position without acid leakage.

- Retains power for long periods of time during storage. 

- Extremely fast recharge capability.

- More power per pound than any other AGM battery.

Congratulations!

Installation Tips

Caution!

Always wear safety glasses and follow the safety 

guidelines below when working around batteries:

Note: The terminal design on the SEA27 allows the direct 

connection of battery terminals without modification.

1. Always disconnect the negative (ground) cable first 

when removing batteries.

2. Connect the negative (ground) cable last when 

installing batteries.

3. Handle and Lift batteries with care. Ensure a good grip 

before lifting.

4. Clean all cable ends and connectors with a wire brush 

or emery cloth until shiny and free from oxidation or 

corrosion.

5. Inspect battery mounting area to be sure it is clean and 

free from objects that could damage the bottom of the 

battery.

6. Replace any corroded connections or worn cables.  

Replace or repaint any corroded hold-downs, shelves or 

trays.

7. If installing batteries in a sealed battery enclosure make 

sure to route tubing from the battery enclosure to outside 

the boat and into open air.  In the event of a charging 

system malfunction, overcharging may occur and the 

tubing will direct gases safely away from the passenger 

compartment.  

8. Use extreme caution when making cable connections 

to the battery.  Extensive damage and dangerous sparks 

will occur if cables are crossed.

9. Tighten connections to a snug fit (do not overtighten).  

Over-tightening can damage the battery and 

VOID THE WARRANTY.  Recheck connections occasionally 

to ensure good connections.

WARNING: 

This product can expose you to chemicals 

including Lead and Sufuric Acid which are known to 

the State of California to cause cancer/birth defects 

or other reproductive harm. For more information go 

to www.P65Warnings.ca.gov.

KEEP OUT OF REACH OF CHILDREN - WASH HANDS AFTER HANDLING

SHIELD EYES

EXPLOSIVE

GASES

CAN CAUSE BLINDNESS OR INJURY

NO

* SPARKS

* FLAMES

* SMOKING

SULFURIC ACID

CAN CAUSE BLINDNESS 

OR SEVERE BURNS

FLUSH EYES

IMMEDIATELY

WITH WATER

GET MEDICAL

HELP FAST

DANGER 

/

POISON

Proper charging is crucial for proper performance of the 

SEA27. We recommend keeping the SEA27’s voltage 

maintained at 12.8 volts (open circuit) by means of a 

properly designed regulated charging system.  If your 

battery has been discharged well below the recommended 

12.8 volts we recommend following chart to the right for 

proper recharging of the SEA27. The charging times stated 

are using an automotive Current Tapering Charger or 

otherwise know as a Constant Voltage Charger. These 

chargers are microprocessor controlled and will regulate 

the charge voltage and current far better than the run of 

the mill automotive power charger. Contact Stinger for 

more information on how to obtain one of these superior 

chargers.

Never use an inexpensive constant current or “trickle” 

charger!  These chargers do not have regulated charging 

abilities. They can overcharge the SEA27 causing severe 

damage to the battery. Even a small amount or .5 amp 

from a trickle charger if left on after the battery is fully 

charged will overcharge the battery. Overcharging will 

overheat and dry out the electrolyte causing the battery to 

fail prematurely. Overcharged batteries are not covered 

under warranty.

An undercharged battery not only has a temporary 

reduction in capacity, if left in an undercharged state or 

continually undercharged, the capacity and life of the 

battery will be permanently reduced.  The battery warranty 

does not cover batteries that fail due to undercharging. For 

this reason we recommend that you keep the battery fully 

charged at all times with a properly designed charging 

system that charges at 13.8 volts for float/standby usage 

and 14.5-15 volts in cyclic applications.

Reviews: