Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
PPTC Devices for Protection of Battery Packs
Post: #1

Lithium ion cells packaged in aluminium cans continue to be the highest performing cells in the market. Circuit protection for rechargeable lithium-based battery cells and packs in a critical design consideration.

overcurrent and overtemperature conduction that can result from accidental shorting or abusive/runaway charging can raise temperature high enough to damage components and cause substantial damage.

This paper presents the use of PPTC devices for short-circuit and overcharge of battery packs. Polymeric positive temperature coefficient [PPTC] devices help to protect circuits by going from a low-resistance state to a high resistance state in response to an overcurrent or overtemperature condition.

Commercially available OEM packs with Li-P and Li-Mn cells are now employing PPTC devices for primary protection.

Laboratory overcharge testing at 25?C,12V demonstrated that PPTC devices reduced maximum cell temperature by 40?-50?C, while also helping to prevent bulging, rupture, seperator melting and cell shut down.

Ultimately, pack designers must decide what level of protection is required for their application and only a system test can determine whether or not a specific protection device is appropriate.

PPTC devices have demonstrated their effectiveness in a wide range of circuit protection applications .Their ability to provide reliable, resettable protection reduces costly warranty returns and
Post: #2
PPTC Devices Used In Battery Packs
Circuit protection for rechargeable lithium-based battery cells and packs is a critical design consideration. accidental shorting or runaway charging can increase the temperatures and cause substantial equipment damage. Earlier systems relied on fragile one-shot fuses a polymeric positive
temperature coefficient (PPTC) device is used as the primary protection as the primary short-circuit and overcharge protection. A secondary passive element in form of thermal or current fuse is also installed.

Evaluation Of Primary PPTC Overcharge Protection In Li-Mn And Li-P Battery Packs
The The Li-Mn and Li-P battery packs were subjected to
2.5 C-12 V overcharge tests with and without PPTC protection. The thermocouples connected to each cell collected the test data. The 2.5 C-12 V overcharge damaged the Li-Mn cell without PPTC. the cell reached a maximum surface temperature of
117°C. In a Li-Mn cell with PPTC protection, the PPTC device interrupted the charge current, held off the excess charge voltage, and the cell
began to cool.

Fine Tuning Thermal Cutoff To Improve Overcharge Protection
the thermal cutoff performance of the device must be matched to the protection needs of the cell so that PPTC device can effectively protect from overcharge.

for further details, refer this pdf:
Post: #3
Post: #4
hi gaddams2[at],
what you wish to say?
Post: #5
pcb layout for temprature controlled fan
Post: #6
to get information about the topic "Devices for Protection of Battery Packs" full report ppt and related topic refer the link bellow

Important Note..!

If you are not satisfied with above reply ,..Please


So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page
Popular Searches: overvoltage protection, systemsopto electronicsoptoelectronixopto electronics lafayetteopto electronicaopto electronics incopto electronics co ltdopt, sensor technology devices, handheld devices, cd protection, meego devices, pptc devices ppt,

Quick Reply
Type your reply to this message here.

Image Verification
Image Verification
(case insensitive)
Please enter the text within the image on the left in to the text box below. This process is used to prevent automated posts.

Possibly Related Threads...
Thread: Author Replies: Views: Last Post
  Surge current protection using superconductors computer science crazy 9 7,867 16-03-2016 12:03 AM
Last Post: computer science crazy
  Surge Current Protection Using Superconductors pradeep.srivatsa 10 6,939 16-03-2016 12:03 AM
Last Post: computer science crazy
Star Surge current protection using superconductors computer science crazy 13 6,691 02-02-2015 04:04 PM
Last Post: Guest
  Stability Analysis for Power Swing Protection seminar surveyer 1 1,613 10-03-2013 07:06 AM
Last Post: Guest
Last Post: seminar details
Last Post: seminar details
  protection of transmission lines using gps full report computer science technology 9 17,864 16-10-2012 01:25 PM
Last Post: seminar details
  Battery charger circuit using SCR. computer girl 0 794 11-06-2012 04:09 PM
Last Post: computer girl
Star Lightning Protection Using LFA-M computer science crazy 6 7,694 02-03-2012 11:19 AM
Last Post: seminar paper
  Protection Of Transmission Systems By Using The Global Positioning System computer science crazy 8 8,226 15-02-2012 04:22 PM
Last Post: santoshdevath