for Lithium Battery Protection Lithium Cell Protection Device - PowerPoint PPT Presentation

MHP-TA Resettable TCO for Lithium Battery Protection

Lithium Cell Protection Device Requirements are Changing  Higher cell capacities & larger cell surface areas • Lower thermal cut-off temperatures (<90C) required • Improved margin of safety needed  Higher battery discharge rates • Hold currents above 6A required • Multiple series and parallel pack configurations  Small & thin protection devices required 2 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

MHP-TA Resettable Thermal Cut-Off (TCO)  What is the MHP-TA Device? Metal Hybrid PPTC - Thermal Activation Device • Combines a Polymer PTC with a Bi-metal in parallel • Over-temperature protection device • Resettable activation  Application: • Protection for rechargeable Lithium cells  Lithium Polymer  Li-ion Prismatic • Other applications that require a resettable TCO • Resistance or laser welded to cell terminals • Nickel lead extensions and taping also available 3 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

The MHP-TA Technology Principle  A hybrid circuit protection device that combines a Polymer PTC (polymeric positive temperature coefficient) with a Bi-metal in parallel  The MHP-TA technology incorporates the best features of a bimetal breaker and PPTC and reduces the downside of each technology. Advantage Disadvantage ・ Low resistance ・ Non-Latching ・ High operating current Bimetal ・ Mechanical contact ・ Good temperature sensing Combine ・ Latches ・ Thermal derating size for PPTC operating current ・ No mechanical contact Metal Hybrid PPTC (MHP) – Thermal Activation 4 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

MHP-TA Technology Leverages TE Strengths  TE strengths in high precision, miniature molded connector products  TE extensive experience in polymer PTCs and battery circuit protection RF Switch Plug TE Connectivity Core Competencies 2.00 (0.079) • Precision molding A 26 (1.024) A • Precision stamping A 2.88 (0.113) 2.00 (0.079) • Unit : mm (inch) Miniaturization Unit : mm (inch) 0.95 (0.037) • High speed assembly 5 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

MHP-TA Application Cell protection – added directly to the Li-polymer cell  Resistance or laser welded to cell terminals  Can also be added to prismatic cells  Nickel lead extensions and taping also available 6 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

MHP-TA Technology Solves These Problems Customer Problem General Design Problem Ultimate Solution Solution Lithium cells need Thermal Cut-off One time use TCOs over temperature (TCO) (thermal fuse) can protection have nuisance trips Resettable thermal Thin PCs and Traditional protection tablets…. protection devices device in a low capable of higher profile package 1.Need higher hold currents (>6A) (MHP-TA) capacity cells than are not small or thin enough a smart phone 2.Generate higher discharge currents 7 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

MHP-TA Operating Principle Normal Condition ① Contact • Silver contacts carries the current [Rc<<Rptc] PPTC Fault Condition ② Contact • Contact opens • Current goes through PPTC PPTC • Current heats up the PPTC >>>> Resistance increases Result: Tripped PPTC heats the bimetal and keeps it open during a fault condition 8 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

Example of Resistance vs. Temperature Curve Contact open temperature test Spec: Contact open at 77 ℃ <Test condition> Rise from 20 ℃ to 120 ℃ and go back to 20 ℃ Temperature step: 2 ℃ 77 ℃ contact open device Hold time: 1min 1.0E+02 1.0E+01 Resistance(ohm) 1.0E+00 Contact open 77 ℃ Reset  Open  1.0E-01 1.0E-02 1.0E-03 20 40 60 80 100 120 Temperature (℃) Contact opens at 77 ℃ 9 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

Typical Hold Current vs. Temperature Performance MHP-TAM15 – High Current Series 10 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

Typical Hold Current vs. Temperature Performance MHP-TAM6 – Low Current Series 11 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

MHP-TA Provides Excellent Cycle Life - Durability Cycle test Spec: <Test condition> Resistance: < 5 mohm Power supply: Open / close cycle: No contact weld DC9V/25A (DC 9 V / 25 A 6000 cycles) Temperature: 25 ℃ No resistance change Cycle time: 6,000 cycle 5 Initial resistance : Typ. 2.50 mohm 4 Resistance(mohms) 3 2 1 No contact weld 0 0.1 1 10 100 1000 10000 After 6000 cycles Number of Cycles 12 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

Product Line-up MHP-TAM6 – Low Current Series MHP-TAM15 – High Current Series 13 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.

MHP-TA Technology Summary  Combines a Polymer PTC with a Bi-metal in parallel  Over-temperature protection device  Resettable activation Device Ratings  9VDC  Low current and high current versions  TCO: 72 ° C, 77 ° C, 82 ° C, 85 ° C, 90 ° C  UL Recognized  Ideal for Lithium polymer battery designs that need a small thermal cut-off (TCO) device that can handle higher currents  Resettable device helps eliminate “nuisance trip” issues occurring in non-resettable thermal fuses or TCOs 14 TE Connectivity Confidential & Proprietary. Do not reproduce or distribute.