20
Safety
Nanophosphate
®
releases only a small amount of heat and oxygen under abusive conditions so cells made using
Nanophosphate chemistry do not exhibit the energetic thermal runaway that metal oxide lithium ion cells
experience. This greatly reduces the likelihood of cascading failure—where an incident in one cell spreads to
adjacent cells—within a battery pack designed with Nanophosphate chemistry. Even if all of a pack’s safety
systems fail, the increased safety inherent to Nanophosphate chemistry provides an additional layer of protection
that reduces the incidence, severity and probability of energetic failures.
That said, proper handling and battery pack design must be followed to make sure the A123 Nanophosphate cells
operate safely. These cells can store significant amounts of energy and (unlike most other types of cells) deliver
this energy very quickly. Appropriate pack design must provide sufficient mechanical and environmental
protection to ensure the cells operate within their proper voltage, current, and temperature limits.
The following minimum safety precautions must be followed at all times. Failure to
follow the following safety instructions may result in personal injuries or damage to
the equipment!
•
Cells must not be subjected to ambient conditions greater than 65 °C while in storage. If this condition
occurs cell life will be degraded.
•
Cells must not be heated to or self-heated to a skin temperature in excess of 85 °C during operation. If this
condition occurs cell life will be degraded or the cell will be rendered inoperable.
•
Cells must not be charged or discharged outside the operating temperature range as stated in the A123
Systems Safety Data Sheet (SDS), which can be accessed from the A123 websites* and reduced charging
limits must be followed for extreme operating temperatures (See the Max Current Tables in Appendix A,
starting on page 61).
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Cells must not be incinerated, nor should they be stored or used near open flames.
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Cells must not be punctured, ruptured, dented, or crushed.
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Cell packaging must not be altered in any way.
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Cells must not be immersed or exposed to water or liquids.
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Never use a mechanism to hold the cells in a way that leads to blocked cell vents. If the vents are blocked,
the gas cannot exit the cell in case of cell failure. Cells shall be mounted in the application in a way that will
not interfere with the vent function on the cell. See Figure 12, on 32; Figure 13, on page 32; and Figure 14,
on page 33.
•
If the cell or battery emits smoke or flames, ventilate the area immediately and avoid breathing the fumes.
See the A123 Systems Safety Data Sheet (SDS)* for additional precautions. Cells must not be subjected to
reverse polarity or short circuited. Individual cell fusing is required in pack designs with cells in parallel to be
compliant with international regulations that are harmonized with the UN Recommendations on the
Transport of Dangerous Goods. UN 38.3, US-DOT and other international shipping regulations.
*The A123 Safety Data Sheet is accessible from the Resources Page on the A123 web sites:
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http://a123energy.com/resources-overview.htm
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http://www.a123systems.com/resources-overview.htm