Alpha Technologies AlphaCell SMU-HR - Manual (Page 10)

745-680-B2-002, Rev. B 10
1.5 Temperature and Battery Life
High temperatures can harm the battery and reduce its lifespan. Battery life decreases by
50% every per 15ºF (~ 9ºC) above the standard operating temperature of 77ºF (25ºC).
To minimize battery damage:
Use temperature compensated chargers. •
Never allow the battery's temperature to exceed +131ºF (+55°C). •
Make sure operating area is properly ventilated, so heat cannot accumulate. •
Provide at least 0.39" (10mm) of space between batteries to enhance convective cooling. •
Visit sites annually to check for shorted cells, improperly set voltages, filter cleaning on •
ventilation systems, etc.
1.6 Internal Resistance and Short-circuit Current
The internal resistance of the battery is affected by temperature and charge state. The
internal resistance is lowest when the battery is fully charged.
Table 1-2, Internal Resistance and Short Circuit Current at 77ºF (25ºC)
Type Internal Resistance (mΩ) Short Circuit Current (A)
SMU-HR 12-9 32.4 370
SMU-HR 12-18 15.0 800
SMU-HR 12-35 10.0 1239
SMU-HR 12-55 8.50 1498
SMU-HR 12-75 6.50 1959
SMU-HR 12-90 5.20 2442
SMU-HR 12-100 5.22 2247
SMU-HR 12-150 4.14 3072
CAUTION!
A short circuit current will decrease the voltage of the battery to 0V, and damage the internal
components.
1.0 Introduction, continued