Thermal Runaway Warning signs and preventive actions Presented by - PowerPoint PPT Presentation

Thermal Runaway Warning signs and preventive actions Presented by Peter DeMar 1

If thermal Thermal runaway runaway does not scare you, then you are… 2

Thermal runaway  Brand new to the stationary battery industry  Ignorant of thermal runaway disasters 3

Thermal runaway  Someone who realizes there are always warning signs  Knows what they are  Is applying the correct preventive measures 4

What is thermal runaway? CAUSED BY  Excess of battery charging current  Produces more internal heat than the battery can dissipate Thermal runaway can be detected , prevented and recovered from 5

Recovery = green benefit RECOVER a battery from thermal runaway and continue to use it  Reduces carbon footprint for that battery  GREEN benefit for the environment  Good for your budget 6

The monster appears unexpectedly? “ It occurred without warning ” 7

The monster appears unexpectedly?  There is ALWAYS an early warning  We just did not understand the signals • They are obvious • There for many months! 8

What are these early warning signs?  Increase in float current • Starts very slowly • Increases over time • Current through the battery • Not necessarily = charger meter 9

What are these early warning signs?  Increase in float current  Gradual increase in the temperature • Starts very slowly differential between • Increases over time cells and ambient • Current through the battery 10

What are these early warning signs?  Increase in float current  Gradual increase in the temperature • Starts very slowly differential between • Increases over time cells and ambient • Current through the battery These two items – when properly checked and tracked – will provide substantial warning so that you can take necessary actions to prevent a thermal runaway 11

What causes thermal runaway?  Negative plate discharge and sulfation  Increase in float current  Dry out of cells  Loss of electrolyte contact through AGM from plate to plate = inability of cells to dissipate internally generated excess heat 12

Preventing thermal runaway  IEEE 1188 standard  Maintain overall float voltage correct for ambient temperature  Track temp. differential between cells and ambient monthly  Track float current monthly Contact us for guidance on what “typical” float current should be for your battery 13

How to take the measurements  Hand held meters  Monitoring, such as the BEM device  Keep accurate records and keep track of records Track readings for the life of the battery 14

Recovery after thermal runaway  Re ‐ establish proper saturation  Remove sulfates from the negative plates  Install catalysts You can take a structurally intact battery from full ‐ blown thermal runaway and turn it back into a usable and reliable battery 15

Preventing thermal runaway  Re ‐ establish proper saturation  Remove sulfates from the negative plates  Install catalysts You can prevent thermal runaway by applying these actions early 16

Who and what  Now that the early warning signs of thermal runaway are so easily observed, just who is responsible when it occurs? 17

Who and what  Now that the early warning signs of thermal runaway are so easily observed, just who is responsible when it occurs? YOU ARE. 18

Who and what  Now that you understand that there is a means of recovering a battery from thermal runaway • You can be pro ‐ active instead of re ‐ active • You have time to determine just what actions are best for you 19

STATIONARY POWER SERVICES FOR INDUSTRY Experts in DC Systems a WBE Enterprise a WBE Enterprise GET IN + For further information please contact us. Contact us today for more information OUCH on how we can help you! Corporate Headquarters Gary L. Brewer President 1313 County Route 1 Oswego, NY 13126 Toll ‐ Free: (800) 221 ‐ 7123 Phone: (315) 342 ‐ 2373 Fax: (315) 342 ‐ 0797 (800) 221 ‐ 7123 (800) 221 ‐ 7123 www.batteryresearch.com www.batteryresearch.com 20