Publication No: EN-ODY-TM-0002 - February 2015
www.odysseybattery.com
14
Table 3 shows the minimum charge currents for the full
range of ODYSSEY batteries when they are used in a deep
cycling application. When using a charger with the IUU
profile, we suggest the following ratings for your ODYSSEY
battery.
Note the charger current in the bulk charge mode
must be 0.4C
10
or more.
Table 3: Battery size and minimum three-step
charger current
Charger
Recommended ODYSSEY
®
Battery Model*
rating, amps
6A
PC310 / PC370 / PC535 / PC545 /
PC625 / PC680
10A
PC925 or smaller battery
15A
PC1200 or smaller battery
25A
PC1500 or smaller battery
25A
PC1700 or smaller battery
40A
PC2150 or smaller battery
50A
PC2250 or smaller battery
Small, portable automotive and powersport chargers may
also be used to charge your ODYSSEY battery. These
chargers are generally designed to bring a discharged
battery to a state of charge (SOC) that is high enough to
crank an engine. Once the engine is successfully cranked,
its alternator should fully charge the battery. It is important
to keep in mind the design limitations of these small
chargers when using them.
Another class of chargers is designed specifically to
maintain a battery in a high SOC. These chargers, normally
in the
3
/
4
amp to 1
1
/
2
amp range, are not big enough to
charge a deeply discharged ODYSSEY
®
battery. They must
only be used either to continuously compensate for parasitic
losses or to maintain a trickle charge on a stored battery, as
long as the correct voltages are applied. It is very important,
therefore, to ensure that the ODYSSEY battery is fully
charged before this type of charger is connected to it.
Effect of undercharge in cycling applications
Proper and adequate charging is necessary to ensure that
ODYSSEY batteries deliver their full design life. Generally
speaking, a full recharge requires about 5% more amp-
hours (Ah) must be put back in than was taken out. In other
words, for each amp-hour extracted from the battery, about
1.05Ah must be put back to complete the recharge.
Cycling tests conducted on an ODYSSEY PC545 battery
demonstrated the impact raising the charge voltage from
14.2V to 14.7V has on the cycle life of the battery. The
results are shown in the graph at right.
Samples 1 and 2 were charged at 14.2V while Samples 3
and 4 were charged at 14.7V. All batteries were discharged
at 2.3A until the terminal voltage dropped to 10.02V and
charged for 16 hours. In this particular test, a capacity of
11.5Ah corresponds to 100% capacity and 9.2Ah is 80%
of rated capacity and the battery is considered to have
reached end of life at that point.
The message to be taken from this graph is clear – in deep
cycling applications it is important to have the charge
voltage set at 14.4 – 15.0V. A nominal setting of 14.7V
is a good choice, as shown by the test results.
(A) Selecting the right charger for your battery
Qualifying portable automotive and powersport chargers
for your ODYSSEY battery is a simple two-step process.
Step 1 Charger output voltage
Determining the charger output voltage is the most important
step in the charger qualification process.
If the voltage output
from the charger is less than 14.2V or more than 15V for a 12V
battery, then do not use the charger
. For 24V battery systems,
the charger output voltage should be between 28.4V and 30V.
If the charger output voltage falls within these voltage limits
when the battery approaches a fully charged state, proceed to
Step 2, otherwise pick another charger.
Step 2 Charger type - automatic or manual
The two broad types of small, portable chargers available
today are classified as either automatic or manual. Automatic
chargers can be further classified as those that charge the
battery up to a certain voltage and then shut off and those
that charge the battery up to a certain voltage and then switch
to a lower float (trickle) voltage.
An example of the first type of automatic charger is one that
charges a battery up to 14.7V, then immediately shuts off.
An example of the second type of automatic charger would
bring the battery up to 14.7V, then switches to a float (trickle)
voltage of 13.6V; it will stay at that level indefinitely. The
second type of automatic charger is preferred, because the
first type of charger will undercharge the battery.
A manual charger typically puts out either a single voltage or
single current level continuously and must be switched off
manually to prevent battery overcharge.
Should you choose
to use a manual charger with your ODYSSEY battery, do not
exceed charge times suggested in Table 5 on the next page. It
is extremely important to ensure the charge voltage does not
exceed 15V
.
0
2.3
4.6
6.9
9.2
11.5
13.8
16.1
0
50
100
150
200
250
300
350
400
450
Amp-hrs out
Cycle
Samples 1 & 2: Given a 24hr CC charge @ 650mA prior to cycle 55, then resumed cycling
Sample 3: Given a 24-hr CC charge @ 650mA at cycle 359, then resumed cycling
Sample 4: Given a 24-hr CC charge @ 650mA at cycle 254, then resumed cycling
Sample 3
Sample 4
Sample 1
Sample 2
* for PC1800, consult EnerSys Technical Department
