A Heating System of Electric Vehicles using Waste Heat of Batteries

Transcription

1 EVS28 KINTEX, Korea, May 3-6, 2015 A Heating System of Electric Vehicles using Waste Heat of Batteries Hyunbin Park, Yeong-Gyo Gim, Minseob Sim, and Shiho Kim School of integrated technology & YICT Yonsei University, 85 Songdo-gwahak-ro, Yonsu-gu, Incheon, , Korea, shiho@yonsei.ac.kr

2 Contents I. Motivation II. Heat generation of PHEV batteries Conventional Battery cooling system III. Proposed Heating system using waste heat IV. Simulation and Experiment results V. Summary & Conclusions ACKNOWLEDGMENT 2

3 Motivation Extending EV range is an important issue. Heat Generation of EV Batteries during driving is significant. Generated Heat is waste by the battery cooling system To extend mileage of EV, we propose a EV heating system using waste heat of Battery. 3

4 Heat generation of PHEV batteries Example Spec. of Plug-in Hybrid Electric Vehicle GM Chevy Volt Battery pact Total rated energy (KWh) 16 Total number of cells 288 Total usable energy (KWh) 9.4 Each cells rated energy (Wh) ( = / 288) Each cells usable energy (Wh) ( = 9400 / 288 ) Chemistry LiMn2O4, 3.8 V Internal resistance of each cell (mω) Min 25 ~ Max 50 Average claimed range, Pure EV mode (mi/km) 35 /

5 Heat generation of PHEV batteries Heat generated in the PHEV Battery C rate [C] 0.25 C 1C 2C Speed (mi /hour) Total energy usage (KWh) Current of each cell (A) Heat generated each cell (W) Total heat generation (Wh) Ratio Total heat/energy usage Min. = 0.12 Min. = 0.24 Min. = Max. = Min. = 1.47 % Max. = 2.94 % Min. = 1.92 Min. = 3.84 Min. = Max. = Min. = 5.9 % Max. = 11.7 % Min. = 7.69 Min. = Min. = Max. = Min. = % Max. = % 5

6 Heat generation of PHEV batteries Waste heat [Wh] Min Max (1C) (2C) (0.25C) Driving speed [mi / hour] The generated heat battery as a function of driving speed of the PHEV 6

7 Conventional Battery cooling system Example of liquid battery cooling system of GM Volt 7

8 Conventional Battery cooling system Typical Battery heating & cooling system 8

9 Proposed Heating system using waste heat Battery Cooler using Heat Pipes Battery Cell Looped Heat pipe thermal fin Liquid Inlet Micro Channel Batter y cell Vapor Outlet Hot vapor transfer-tube 9

10 Proposed Heating system using waste heat Structure of Heat Spreader Vapor Chamber Heat sink Vapor Inlet Vapor Chamber Liquid Outlet Wick 10

11 Proposed Heating system using waste heat Heated seats Back pressure regulater Thermal fin for battery cell cooling Flow control valve (hot vopor) Heated seats flow control valve Liquid chamber Flow control valve (cool liquid) Heat Spreader (normal cooling mode) Proposed heating system using waste heat 11

12 Proposed Heating system using waste heat Flow Control Valve (Liquid) C A Heated Seats Heat Pipes (heat source) Heat Spreader & Fluid Chamber (Condenser) A C B Cabin Flow Control Valve B A Normal mode Flow Control Valve (Vapor) Pump& Chiller B C Battery max. cooling Mode Cabin heating mode Liquid flow Vapor flow Architecture of the proposed system 12

13 Proposed Heating system using waste heat Heated seat Flow control valve Heat spreader Battery cells Folw control valve(liquid) Folw control valve(vapor) 13

14 Summary & Conclusions The average waste heat of EV battery due to Joule heating is calculated to be more than 2KW during normal driving mode. This waste heat might be a valuable regenerative heating source of electric vehicles. A cabin heating system of EVs using waste heat of batteries was proposed. The proposed cooling system has 3 modes : Normal temperature level cooling using LHP without additional consumption of operating power, High temperature level cooling using a chiller, and Cabin heating using waste battery heat. 14

15 Summary & Conclusions The proposed system consists of multiple evaporator loop heat pipes(lhp) for battery cooling and cabin heating simultaneously. The proposed heating system is combined with a selfconvectional battery cooling system using looped heat pipes(lhp). The main advantage of the proposed cooling system A noiseless system operating without additional power consumption in normal driving mode. 15

16 ACKNOWLEDGMENT This research was supported by the Ministry of Science, ICT, and Future Planning (MSIP), Korea, under the IT Consilience Creative Program (NIPA-2014-H ) supervised by the National IT Industry Promotion Agency (NIPA). 16