Renata SA Electrical & Temperature Performance - Manual

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the swiss power source
Electrical & Temp. Performance
Pulse discharge characteristics
RENATA Lithium batteries have excellent pulse
load characteristics, for example for the
transmission of radio signals by remote controls.
The following diagrams show the voltage
characteristics at pulse loads of 10, 20, and 50 mA during 100 ms, pulse cycle 1 second, at
ambient temperature. The voltage drop under load
is evident as well as the voltage recovery to
almost the original level after a very short time.
Please contact Renata for further details.
Inverse current
Lithium primary batteries are not rechargeable.
Therefore, if there is a possibility of electric
current flowing from the main power source to the
battery, the circuit must include two suitable
blocking diodes in series or one blocking diode
and one protective resistor in series (refer to
drawing in chapter SAFETY GUIDELINES) Use a
silicium diode of small inverse current to prevent
charging. The total amount of recharge energy
due to leakage by the blocking diodes should not
exceed 1% of the battery's nominal capacity
during its total service life. A higher input of re-
charge energy may harm the battery or reduce its
performance.
Example: A CR2450N battery with a nominal
capacity of 540 mAh is expected to supply power
for 5 years. The amount of tolerable re-charge
energy is 5.4 mAh, corresponding to an inverse
current of 0.123 µA for the total service life
1) .
Consequently, a blocking diode with an inverse
current not greater than 0.1 µA should be
selected. Please note that the inverse current of
blocking diodes varies with temperature.
Short circuits
When lithium batteries are short-circuited, it takes
time for the battery voltage to recover, even in
case of slight short-circuits. If electrical characte-
ristics are measured while the battery is recover-
ing, the battery may appear to be defective, but is
not. Short-circuiting leads to deterioration of the
cell capacity. Short-circuiting of batteries must
therefore be avoided, except for wave or dip
soldering. Use an instrument with a high input
impedance (minimum 10 M
⏲ ) for measuring
open circuit voltage.
U
2
(V
)
Time (s)
load Impulsions 100ms, l= 10 mA at 23°C CR2032MFR
0 1 2 3 4 5 6 7 8 9 10
3.5
3
2.5
2
1.5
1
U
2
(V
)
Time (s)
load Impulsions 100ms, l= 20 mA at 23°C CR2032MFR
0 1 2 3 4 5 6 7 8 9 10
3.5
3
2.5
2
1.5
1
U
2
(V
)
Time (s)
load Impulsions 100ms, l= 50 mA at 23°C CR2032MFR
0 1 2 3 4 5 6 7 8 9 10
3.5
3
2.5
2
1.5
1
1) 540 mAh * 1% = 5.4 mAh
5.4 mAh / (5 years * 365 days * 24 hours) = 0.123 µA
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