CN104577254B - A kind of Thermal Management System for EV Battery Packs and method of work thereof - Google Patents

A kind of Thermal Management System for EV Battery Packs and method of work thereof Download PDF

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CN104577254B
CN104577254B CN201410809272.6A CN201410809272A CN104577254B CN 104577254 B CN104577254 B CN 104577254B CN 201410809272 A CN201410809272 A CN 201410809272A CN 104577254 B CN104577254 B CN 104577254B
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heat
switch valve
battery
cells
temperature
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CN104577254A (en
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闵海涛
孙维毅
于远彬
王鹏宇
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Jilin University
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Jilin University
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Abstract

The invention discloses a kind of pure electric automobile battery pack thermal management system and method for work thereof, including the case liquid circulating passage footpath being positioned at Battery case within be positioned at the liquid circulating passage footpath case outside Battery case Wai;In case, liquid circulating passage footpath includes heating unit A, heat exchanger A, hydraulic pump A, three-way valve A and assignment of traffic unit;The outer liquid circulating passage footpath of case includes fuel heater, switch valve, switch valve C, heat exchanger B, switch valve A, three-way valve B, radiator, air conditioning system, fluid reservoir and switch valve D.Battery system is made to remain under good operating temperature under charged state and different transport conditions, ensure the temperature equalization between each battery cell and reduce the heat management energy consumption of battery system, thus ensure to use rational heat management mode that battery system is carried out heat management under different vehicle-states, extend the service life of battery system, reduce use cost and the car load energy consumption of battery of electric vehicle.

Description

A kind of Thermal Management System for EV Battery Packs and method of work thereof
Technical field
The invention belongs to batteries of electric automobile field of heat management, be more particularly to a kind of batteries of electric automobile group heat Management system, it is adaptable to electrokinetic cell heat management during charging and discharging.
Background technology
Battery is the critical component of electric automobile, directly influences the performance of electric automobile.And the work of battery Temperature has vital impact for the service life of battery and the performance of battery.The too low meeting of temperature makes electricity Tank discharge power and capacity are affected, and cause vehicle performance to be greatly reduced;Temperature is too high, the circulating battery longevity Life will be affected, and therefore battery be carried out heat management and be very important.
Chinese patent literature discloses the battery thermal management system of Application No. 201110210364.9, this system The the first liquid closed circuit being made up of battery bag, water tank, water pump and radiator, between water pump and battery bag It is sequentially connected with cooling structure and heater to constitute the second liquid closed circuit, at the first liquid closed circuit and second Liquid closed circuit is provided with the electromagnetic valve only controlling respective liquid closed circuit, wraps at battery and is provided with temperature sensing Device, battery management unit, temperature sensor, water pump, the first electromagnetic valve, the second electromagnetic valve, cooling structure All being connected with entire car controller with heater, entire car controller receives the detection signal of temperature sensor and controls Water pump, two electromagnetic valves, cooling structure, heater and battery management unit work, so that battery wraps in Reasonably temperature work.But this invention has the disadvantage that 1, this invention uses Electric heating conduct Unique mode of heating of set of cells heating, in case of a cold start, does not explain in detail the energy of heater Amount source;2, heater and refrigerator device are connected in the same circuit and do not take to protect by this invention Temperature measure, meanwhile, whole circulation line is longer, therefore, in the case of ambient temperature is relatively low, by Radiating effect in chiller and circulation line can cause the loss of energy, reduces the work efficiency of system;3、 In the case of this system enables air conditioner refrigerating cooling and radiator cooling at the same time, at chiller and radiator In position relationship in parallel, and the fluid flow of the cooled device of convection current and radiator is not had to enter in the invention Row controls, and causes the control imperfection to cooling procedure.
At present, the heater of most of heat management systems is Electric heating, and at low ambient temperatures, electricity The energy source of heater has the biggest problem, if using the electricity of set of cells self that it is heated, Do not reach suitable operating temperature due to set of cells at the beginning, therefore set of cells can be produced bigger injury, Simultaneously because the consumption of electricity, also reduce the flying power of electric motor car.
Meanwhile, the working life of whole set of cells is also had the biggest by the temperature contrast between different battery cells Impact, although had certain methods to go to solve this problem, but the temperature equalization problem between battery cell Still await having been resolved further.It addition, for the most quickly making battery reach suitable under low temperature environment Operating temperature thus to meet the driving conditions of electric automobile be also the problem that needs solve.
Summary of the invention
The technical problem to be solved is to provide a kind of Thermal Management System for EV Battery Packs and work thereof Make method, make battery system remain at good work under charged state and different transport conditions At a temperature of, it is ensured that the temperature equalization between each battery cell and the heat management energy consumption of reduction battery system, from And ensure to use rational heat management mode that battery system is carried out heat pipe under different vehicle-states Reason, extends the service life of battery system, reduces use cost and the car load energy consumption of battery of electric vehicle.
For solving the problems referred to above, the technical scheme of battery of electric vehicle heat management system employed herein is, knot Conjunction accompanying drawing:
A kind of Thermal Management System for EV Battery Packs, including Battery case 1, set of cells 2, control unit 19, Set of cells 2 is arranged in Battery case 1, and set of cells 2 is made up of at least two battery module, each battery Module includes at least two battery cell;This system includes the case liquid circulation being positioned within Battery case 1 Path and be positioned at the liquid circulating passage footpath case outside Battery case 1 Wai;
Wherein, in case, liquid circulating passage footpath includes heating unit A3, heat exchanger A4, hydraulic pump A5, threeway Valve A6 and assignment of traffic unit 7;Heating unit A3 is connected with heat exchanger A4, heat exchanger A4 and battery The battery cell of group 2 fits tightly, and will flow through the heat of heat-exchange fluid therein and the heat of battery cell Amount swaps;Three-way valve A6 entrance is connected with hydraulic pump A5, and an outlet is connected with heating unit A3, The outer liquid circulating passage footpath of case of Battery case 1 is led in another outlet;Assignment of traffic unit 7 is to flowing through wherein Heat-exchange fluid carry out assignment of traffic, assignment of traffic unit 7 entrance is connected with hydraulic pump A5, outlet with Heat exchanger A4 is connected;
The outer liquid circulating passage footpath of case includes fuel heater 8, switch valve B9, switch valve C10, heat exchanger B11, switch valve A12, three-way valve B13, radiator 14, air conditioning system 20, fluid reservoir 21 and switch valve D22;Switch valve B9 and switch valve C10 is all connected with the same outlet of three-way valve A, switch valve B9 another End is connected with fuel heater 8, and the switch valve C10 other end is connected with heat exchanger B11;Switch valve A12 It is connected between air conditioning system 20 and heat exchanger B11, constitutes the fluid loop of air conditioning system 20;Heat is handed over Parallel operation B11 is connected with the entrance of three-way valve B13 simultaneously, and two outlets of three-way valve B13 connect heat radiation respectively Device 14 and hydraulic pump B16;Switch valve D22 one end is connected with heating unit A3, the other end and fluid reservoir 21 It is connected with fuel heater 8;Fluid reservoir 21 connects fuel heater 8, hydraulic pump B16 and radiator respectively 14;Radiator 14 is configured with fan 15;
It is distributed with temperature sensing in liquid circulating passage footpath and the outer liquid circulating passage footpath of case in Battery case 1, case Device;
This system also includes charger 17, is realized the source of heat management system electric energy by electromagnetic switch 18, when When charger 17 is connected with electrical network, electromagnetic switch 18 is connected with charger 17, is electricity by grid side electric energy Pond heat management system is powered, and when charger 17 is not connected with electrical network, electromagnetic switch 18 is with set of cells 2 even Connect, powered for battery thermal management system by set of cells 2.
The improvement project of described a kind of Thermal Management System for EV Battery Packs, described heat exchanger A4 is by many Individual heat exchange module forms, the corresponding battery module of each heat exchange module, independent between each Switching Module Work, carries out heat management for corresponding battery module.
The improvement project of described a kind of Thermal Management System for EV Battery Packs, described assignment of traffic unit 7 It is provided with an entrance and multiple outlet, each outlet and heat exchanger A4 corresponding connection of heat exchange module, The flow of its each outlet is allocated by assignment of traffic unit 7.
The improvement project of described a kind of Thermal Management System for EV Battery Packs, described heating unit uses electricity Heating.
Present invention simultaneously provides the method for work of a kind of Thermal Management System for EV Battery Packs, it includes parallel Heat management process and battery temperature balance control process;
Wherein, heat management process comprises the following steps:
Step one, judge the ambient temperature of system: preset four temperature thresholds, the temperature of four temperature thresholds Value is followed successively by the second temperature threshold, the first temperature threshold, the 3rd temperature threshold, the 4th temperature threshold from low to high Value, compares with four temperature thresholds in real time by the temperature of set of cells 2;
Step 2, when set of cells 2 temperature less than the first temperature threshold time, need set of cells 2 is heated:
1) whether first detection electric motor car is in charged state;
1.1) if electric motor car is in charged state:
Enable the first blood circulation: now three-way valve A6 outlet and heating unit A3 UNICOM, single by heating Heat-exchange fluid is heated by unit A3, and drives heat-exchange fluid inside battery case by hydraulic pump A5 Circulation, completes the heating to set of cells 2;
1.2) if electric motor car is not at charged state:
1.2.1) if set of cells 2 temperature is higher than the second temperature threshold, the first blood circulation is started: by adding Heat-exchange fluid is heated by hot cell A3, and drives heat-exchange fluid at battery case by hydraulic pump A5 Inner loop, completes the heating to set of cells 2;
1.2.2) if the temperature of set of cells 2 is less than the second temperature threshold, the second blood circulation is started: now Three-way valve A6 outlet is to switch valve B9 and switch valve C10, and switch valve B opens, and switch valve C10 closes Closing, switch valve D22 opens, and is heated heat-exchange fluid by fuel heater 8, heating unit A3 Not working, hydraulic pump A5 drives heat-exchange fluid to flow through fuel heater 8, through the heat-exchange fluid of heating During flowing through heat exchanger A4, set of cells 2 is heated;
Step 3, when set of cells 2 temperature higher than three temperature thresholds time, set of cells 2 is cooled down:
1) if set of cells 2 temperature is less than the 4th temperature threshold higher than the 3rd temperature threshold, start the 3rd and follow Loop systems: three-way valve A6 outlet UNICOM to switch valve B9 and switch valve C10, and switch valve B9 close, open Closing valve C10 to open, switch valve D22 opens, three-way valve B13 entrance and heat exchanger B11 UNICOM, threeway Valve B13 exports UNICOM and closes to radiator 14, switch valve A12;Hydraulic pump A5 drives heat-exchange fluid to flow through Radiator 14, it is achieved the cooling to set of cells 2;
2) if set of cells 2 temperature is higher than the 4th temperature threshold, the 4th blood circulation is started: the described 3rd On the basis of blood circulation, switch valve A12 is in the cooling condition of opening and air conditioning system 20 and opens; Controller controls air conditioning system 20 and freezes, and switch valve A12 opens, and cold-producing medium is in the driving of air conditioning system 20 Under flow through heat exchanger B11;Meanwhile, heat-exchange fluid under the driving of hydraulic pump A5 from heat exchanger A4 Flow out, be then passed through radiator 14 and tentatively dispel the heat, again pass through heat exchanger B, and with air conditioning system 20 In cold-producing medium realize heat exchange, thus realize the cooling to set of cells 2.
The improvement project of the method for work of described a kind of Thermal Management System for EV Battery Packs, described heat pipe During reason, when interior is heated by needs, start the 5th blood circulation: now three-way valve A6 not with Switch valve B9 and switch valve C10 connects, and switch valve A12, switch valve B9, switch valve C10 all open, Switch valve D22 closes, three-way valve B13 UNICOM to hydraulic pump B16;Heat-exchange fluid drives hydraulic pump B16's Under Dong, flow through fuel heater 8 and be heated, and then flow into heat friendship by switch valve B and switch valve C10 Parallel operation B11;Meanwhile, air conditioning system 20 drive cold-producing medium through switch valve A12 inflow heat exchanger B11, Heat-exchange fluid and cold-producing medium is made to realize heat exchange in heat exchanger B11.
The improvement project of the method for work of described a kind of Thermal Management System for EV Battery Packs, described battery Temperature balance control process refers to: the mean temperature of control unit 19 battery module each to set of cells 2 is with whole The mean temperature of set of cells 2 compares, and is controlled flow allocation unit 7 according to comparative result, adjusts Rectification enters the flow of the heat-exchange fluid of each battery module, to realize in set of cells 2 temperature between each battery module Degree equilibrium.
The present invention provides a kind of Thermal Management System for EV Battery Packs and method of work thereof, makes battery system exist Remain under charged state and different transport conditions under good operating temperature, it is ensured that each battery list Temperature equalization between body and the heat management energy consumption of reduction battery system, thus ensure at different vehicle shapes Can use rational heat management mode that battery system carries out heat management under state, extend making of battery system With the life-span, reduce use cost and the car load energy consumption of battery of electric vehicle.
Accompanying drawing explanation
Fig. 1 is a kind of Thermal Management System for EV Battery Packs structural representation;
Fig. 2 is a kind of Thermal Management System for EV Battery Packs the first blood circulation schematic diagram;
Fig. 3 is a kind of Thermal Management System for EV Battery Packs the second blood circulation schematic diagram;
Fig. 4 is a kind of Thermal Management System for EV Battery Packs third circulation system schematic diagram;
Fig. 5 is a kind of Thermal Management System for EV Battery Packs the 4th blood circulation schematic diagram;
Fig. 6 is a kind of Thermal Management System for EV Battery Packs the 5th blood circulation schematic diagram;
Fig. 7 is a kind of Thermal Management System for EV Battery Packs heat management process flow diagram flow chart;
Fig. 8 is a kind of Thermal Management System for EV Battery Packs flow distributing system structural representation;
Fig. 9 is that a kind of Thermal Management System for EV Battery Packs assignment of traffic controls schematic diagram.
In figure:
1-Battery case, 2-set of cells, 3-heating unit A, 4-heat exchanger A, 5-hydraulic pump A, 6-tri- Logical valve A, 7-assignment of traffic unit, 8-fuel heater, 9-switch valve B, 10-switch valve C, 11-heat is handed over Parallel operation B, 12-switch valve A, 13-three-way valve B, 14-radiator, 15-fan, 16-hydraulic pump B, 17- Charger, 18-electromagnetic switch, 19-control unit, 20-air conditioning system, 21-fluid reservoir, 22-switch valve D
Detailed description of the invention
Describe technical scheme below in conjunction with the accompanying drawings in detail.
A kind of Thermal Management System for EV Battery Packs, as shown in Figure 1, whole system is mainly by with bottom It is grouped into, including:
Battery case 1, Battery case 1 inwall scribbles adiabator, so that Battery case 1 has, and effect is thermally isolated Really;
Set of cells 2, is arranged in Battery case 1, and set of cells 2 is made up of at least two battery module A, B, Each battery module includes at least two battery cell;
It is positioned at the case liquid circulating passage footpath within Battery case 1, specifically includes that
Heating unit A3, it is connected with heat exchanger A4, and heating unit A3 uses Electric heating, such as Resistance wire, Electric radiant Heating Film etc.;
Heat exchanger A4, fits tightly with the battery cell of set of cells 2, and will flow through heat exchange flow therein The heat of body swaps with the heat of battery cell, thus heats battery cell or cool down.Heat Exchanger A4 is divided into different heat exchange module A-A, A-B, works alone between each heat exchange module, each Heat exchange module correspond to a battery module, and be responsible for this battery module and carry out heat management, so, The heat management of different battery modules can individually be carried out.
Hydraulic pump A5, is positioned at the inside of Battery case 1, with assignment of traffic unit 7;
Three-way valve A, its entrance is connected with hydraulic pump A, and an outlet is connected with heating unit A, another The outside of Battery case 1 is led in outlet, for the outer liquid circulating passage footpath of connecting box.
Assignment of traffic unit 7, carries out assignment of traffic to flowing through heat-exchange fluid therein.As it is shown in fig. 7, stream Amount allocation unit 7 has an entrance and multiple outlet, and entrance is connected with hydraulic pump A5, each outlet and heat One heat exchange module of exchanger A4 is connected;Assignment of traffic unit 7 can realize the flow to each outlet It is allocated, thus controls the flow of the heat-exchange fluid of each heat exchange module of inflow heat exchanger A4, enter And each battery module is carried out heat management targetedly.
It is positioned at the liquid circulating passage footpath case outside Battery case 1 Wai, specifically includes that
Fuel heater 8, this heating unit uses fuel mode of heating to carry out flowing through heat-exchange fluid therein Heating, the fuel of employing is usually ethanol or gasoline etc..
Switch valve B9, one end is connected with an outlet of three-way valve A, and one end is connected with fuel heater 8;
Switch valve C10, one end is connected with an outlet of three-way valve A, and switch valve B9 and switch valve C10 Being connected with the same outlet of three-way valve A, the other end is connected with heat exchanger B11;
Heat exchanger B11, is connected with the fluid loop of air conditioning system 20, simultaneously with battery thermal management system Fluid loop connects, thus plays the work carrying out heat exchange between air conditioning system 20 and battery thermal management system With;
Switch valve A12, is connected between air conditioning system 20 and heat exchanger B11, controls air conditioning system 20 In cold-producing medium circulation in heat exchanger B11;
Three-way valve B13, entrance is connected with heat exchanger B11, outlet respectively with radiator 14 and hydraulic pump B16 Connect;
Radiator 14, has fin structure, dispels the heat to flowing through heat-exchange fluid therein;With radiator 14 are configured with fan 15, to accelerate the radiating rate of radiator 14;
Fluid reservoir 21, it connects fuel heater 8, hydraulic pump B16 and radiator 14 respectively;
Switch valve D22, its one end is connected with heating unit A3, one end and fluid reservoir 21 and fuel heater 8 It is connected;
Meanwhile, the some positions in each battery cell surface, heat exchanger A, the conjunction outside Battery case 1 Right position is put and is disposed with several temperature sensors, respectively surface temperature, the heat exchanger A to each battery cell In the profiling temperatures of heat exchanger fluid and ambient temperature equitemperature information detect;In order to make Fig. 1 The most understandable, the most do not mark the particular location of each temperature sensor.
In addition to two above-mentioned fluid loops, the battery thermal management system of the present invention also includes that one controls back Road and a current supply circuit;
Control loop mainly to be divided with hydraulic pump A, three-way valve A, heating unit A, flow by control unit 19 Join unit 7, switch valve A12, switch valve B9, switch valve C10, fuel heater 8, air conditioning system 20, Hydraulic pump B, three-way valve B13, electromagnetic switch 18, charger 17, each temperature sensor and fan 15 etc. It is connected and forms, by control unit 19, above-mentioned each element is controlled.
Current supply circuit has two kinds of power supply modes, and one is to be powered by grid side electric energy by charger 17, Another kind is to use set of cells 2 to power, and the switching of both power supply modes is controlled electromagnetism by control unit 19 and opens The switching of pass 18 completes.When charger 17 is connected with electrical network, electromagnetic switch 18 is with charger 17 even Connect, be that battery thermal management system is powered by grid side electric energy, when charger 17 is not connected with electrical network, electricity Magnetic switch 18 is connected with set of cells 2, is powered for battery thermal management system by set of cells 2.Control unit 19 Itself is powered by set of cells 2 always.Hydraulic pump A, three-way valve A, heating unit A, assignment of traffic unit 7, Switch valve A, switch valve B9, switch valve C10, air conditioning system 20, hydraulic pump B, three-way valve B, electromagnetism The devices such as switch 18, charger 17, each temperature sensor and fan 15 all electrically connect with this current supply circuit.
The mode of operation of the present invention a kind of Thermal Management System for EV Battery Packs is described in detail below.
By to three-way valve A6, switch valve A12, switch valve B, switch valve C10, three-way valve B13, hydraulic pressure Pump A5 and the control of hydraulic pump B16, the battery thermal management system of the present invention has 5 kinds of mode of operations:
First blood circulation pattern: now three-way valve A6 entrance and hydraulic pump A5 UNICOM, three-way valve A6 exports With heating unit A3 UNICOM;Hydraulic pump A5, three-way valve A6, heating unit A3, heat exchanger A4 and stream Amount allocation unit 7 constitutes the internal circulation system of heat management system, and the referred to as first blood circulation, such as Fig. 2 Shown in.First blood circulation is mainly used in the heating to set of cells 2.This fluid circulation system is fully located at electricity Pond casing 1 is internal, has the advantages that to be not easily susceptible to ambient temperature impact.
Second blood circulation pattern: now three-way valve A6 entrance and hydraulic pump A5 UNICOM, three-way valve A6 exports Being communicated to switch valve B9 and switch valve C10, and switch valve B opens, switch valve C10 closes, switch valve D22 Open;Hydraulic pump A5, three-way valve A6, switch valve B, fuel heater 8, heating unit A3, heat exchange Device A4 and assignment of traffic unit 7 constitute the second blood circulation, as shown in Figure 3.Second blood circulation master It is used for the heating to set of cells 2.In this mode, fuel heater 8 is connected in parallel on Battery case 1 outside And very close to Battery case 1, the advantage of this arrangement is to shorten the length of whole liquid circulation, Decreasing thermal loss, simultaneously because pipeline is shorter, the heat-exchange fluid being therefore present in pipeline is less, The firing rate to heat-exchange fluid can be improved, it is achieved the quick heating to set of cells 2.
Third circulation system pattern: now three-way valve A6 entrance and hydraulic pump A5 UNICOM, three-way valve A6 exports UNICOM is to switch valve B9 and switch valve C10, and switch valve B9 closes, and switch valve C10 opens, switch valve D22 opens, three-way valve B13 entrance and heat exchanger B11 UNICOM, and three-way valve B13 outlet UNICOM is to radiator 14, switch valve A12 close;Hydraulic pump A5, three-way valve A6, switch valve C10, three-way valve B13, heat radiation Device 14, fluid reservoir 21, heating unit A3, heat exchanger A4 and assignment of traffic unit 7 constitute the 3rd Blood circulation, as shown in Figure 4.Third circulation system is mainly used in the cooling to set of cells 2, in this pattern Under, heating unit A3 does not works.Now, the heat that set of cells 2 produces is in the friendship through over-heat-exchanger A4 After changing, being dispersed in environment by radiator 14, fan 15 plays the work strengthening radiator 14 radiating effect With.Simultaneously as the pipeline of whole system is longer and has the existence of fluid reservoir 21, therefore, at the 3rd liquid Under state of cyclic operation, the heat exchanger fluid in fluid loop is more, can play buffer battery to a certain extent Organize stablizing of the effect of 2 variations in temperature, beneficially set of cells 2 temperature.
4th blood circulation pattern: on the basis of third circulation system, switch valve A12 is in opening And the cooling condition unlatching of air conditioning system 20, then it is the 4th blood circulation of the battery thermal management system of the present invention, As shown in Figure 5.This operating mode is for quickly cooling down set of cells 2.Now, the heat that set of cells 2 produces On the one hand amount is dispersed in environment via radiator 14, on the other hand, when heat-exchange fluid is through heat exchanger B Time middle, the heat-exchange fluid in heat management loop produces heat exchange with the cold-producing medium of air conditioning system 20, and temperature drops Low, play refrigeration, to strengthen the cooling effect to set of cells 2.
5th blood circulation pattern: now three-way valve A6 is not connected with switch valve B9 and switch valve C10, and Switch valve A12, switch valve B9, switch valve C10 all open, and switch valve D22 closes, and three-way valve B13 joins Pass to hydraulic pump B16;Fuel heater 8, switch valve B, switch valve C10, heat exchanger B11, three-way valve B13, hydraulic pump B16, fluid reservoir 21, switch valve A12 and air conditioning system 20 constitute the 5th cyclic system System, as shown in Figure 6.This operating mode is for heating the cold-producing medium in air conditioning system 20, and then is compartment Heating provide heat.Under this operating mode, hydraulic pump B16 drives flow of heat exchange fluid, works as heat exchange flow Body is heated when fuel heater 8, and then when flowing through heat exchanger B11 and in air conditioning system 20 Cold-producing medium produces heat exchange, provides heat for air conditioning system 20, thus for providing heat in compartment.
The work of a kind of Thermal Management System for EV Battery Packs of the present invention is described in detail below in conjunction with mode of operation Method.
The work process of a kind of Thermal Management System for EV Battery Packs includes parallel heat management process and battery Temperature balance control process.
As it is shown in fig. 7, heat management process comprises the following steps:
Step one, first determine whether the ambient temperature of system, when the temperature of the surroundings is low, need set of cells 2 Carry out heat treated, and when ambient temperature is higher, need set of cells 2 is carried out cooling process.Judging During ambient temperature, preset four temperature thresholds, first threshold and Second Threshold temperature relatively low, be used for judging Set of cells 2 is the need of heating, and the second temperature threshold is less than the second temperature threshold;3rd temperature threshold and 4th temperature threshold temperature is higher, be used for judging set of cells 2 the need of cooling, and the 4th temperature threshold is high In the 3rd temperature threshold;The temperature of set of cells 2 is compared in real time with temperature threshold.
Step 2, when detecting the temperature of set of cells 2 less than the first temperature threshold, need set of cells 2 Heat:
1) whether first detection electric motor car is in charged state;
1.1) if electric motor car is in charged state:
Enable the first blood circulation, by heating unit A3, heat-exchange fluid is heated, and pass through hydraulic pressure Pump A5 drives heat-exchange fluid in battery case inner loop, completes the heating to set of cells 2.
1.2) if electric motor car is not at charged state:
1.2.1) if set of cells 2 temperature is higher than the second temperature threshold, then start the first blood circulation, pass through Heat-exchange fluid is heated by heating unit A3, and drives heat-exchange fluid at battery by hydraulic pump A5 Case inner loop, completes the heating to set of cells 2.Described second temperature threshold is less than the first temperature threshold.
1.2.2) if the temperature of set of cells 2 is less than the second temperature threshold, then the second blood circulation is started, logical Cross fuel heater 8 heat-exchange fluid is heated.Now, heating unit A3 does not works, hydraulic pump A5 Driving heat-exchange fluid to flow through fuel heater 8, the heat-exchange fluid through heating is flowing through heat exchanger A4 During set of cells 2 is heated.Owing to fuel heater 8 is close to Battery case 1, whole second follows The circulating path of loop systems is shorter, and firing rate is fast, and energy loss is little, it is possible to achieve fast to set of cells 2 Speed heating.
Step 3, when ambient temperature is higher or during the high-power traveling of electric motor car, needs to carry out set of cells 2 Cooling:
When detecting set of cells 2 temperature higher than three temperature thresholds, set of cells 2 is cooled down:
1) if set of cells 2 temperature is less than the 4th temperature threshold higher than the 3rd temperature threshold, start the 3rd and follow Loop systems, hydraulic pump A5 drives heat-exchange fluid to flow through radiator 14, and to heat under the effect of fan 15 Exchange fluid cools down, it is achieved the cooling to set of cells 2;Described 4th temperature threshold is higher than the 3rd temperature Threshold value.
Under some thermal extremes weather or under the operating mode such as the lasting high-power traveling of electric motor car, radiator 14 Heat radiation power cooling to set of cells 2 can not be fully achieved, now, start the 4th blood circulation.
2) if set of cells 2 temperature is higher than the 4th temperature threshold, the 4th blood circulation is started.In the 4th circulation Under system condition, controller controls air conditioning system 20 and freezes, and switch valve A12 opens, and cold-producing medium is in air-conditioning system Heat exchanger B is flowed through under the driving of system 20.Meanwhile, heat-exchange fluid is handed over from heat under the driving of hydraulic pump A5 Parallel operation A4 flows out, is then passed through radiator 14 and tentatively dispels the heat, then pass through heat exchanger B, and with Cold-producing medium in air conditioning system 20 realizes heat exchange, thus realizes the cooling to set of cells 2.
At ambient temperature ratio in the case of relatively low, if needing interior is heated, it is possible to use battery heat Fuel heater 8 assisted air conditioning system 20 in management system realizes the heating to interior.Now, open Dynamic 5th blood circulation.Heat-exchange fluid, under the driving of hydraulic pump B16, flows through fuel heater 8 and quilt Heating, and then by switch valve B and switch valve C10 inflow heat exchanger B11.Meanwhile, air conditioning system 20 Cold-producing medium is driven to hand in heat through switch valve A12 inflow heat exchanger B11, such heat-exchange fluid and cold-producing medium Parallel operation B11 realizes heat exchange, it is achieved thereby that provide heat by fuel heater 8 for air conditioning system 20, To improve the speed that heats of air conditioning system 20, promote the comfortableness of occupant.
For first, second, third and the 4th state of cyclic operation of blood circulation, at whole heat management system Work process in, carry out set of cells 2 temperature balance control in real time:
The mean temperature of control unit 19 battery module each to set of cells 2 and the mean temperature of whole set of cells 2 Compare, according to comparative result, flow allocation unit 7 is controlled, adjust and flow into each battery module The flow of heat-exchange fluid, to realize in set of cells 2 temperature equalization between each battery module.Set of cells 2 temperature It is to carry out parallel and through during whole heat management that degree balance controls with above-mentioned heat management process.
As shown in Figure 8, assignment of traffic unit 7, set of cells 2 and heat exchanger A4 constitute flow distributing system, One embodiment of assignment of traffic unit 7 work process is as it is shown in figure 9, opening the first blood circulation pair When set of cells 2 heats, if the mean temperature of battery module A is less than the mean temperature of set of cells 2, The mean temperature of battery module B higher than the mean temperature of set of cells 2, then controls flow by control unit 19 Allocation unit 7, increases the heat of the corresponding module A-A flowing into the heat exchanger A4 corresponding with battery module A The flow of exchange fluid, reduces the corresponding module A-B flowing into the heat exchange A corresponding with battery module B simultaneously The flow of heat-exchange fluid.The design of flow controlling unit 19 can use flow valve to realize continuous print flow Control or use switch valve by switch valve be switched on and off realize adjust stream effect.

Claims (7)

1. a Thermal Management System for EV Battery Packs, including Battery case (1), set of cells (2), control Unit processed (19), set of cells (2) is arranged in Battery case (1), and set of cells (2) is by least two Battery module forms, and each battery module includes at least two battery cell;It is characterized in that, this system bag Include and be positioned at the internal case liquid circulating passage footpath of Battery case (1) and be positioned at the case that Battery case (1) is outside Outer liquid circulating passage footpath;
Wherein, in case, liquid circulating passage footpath includes heating unit A (3), heat exchanger A (4), hydraulic pump A (5), three-way valve A (6) and assignment of traffic unit (7);Heating unit A (3) and heat exchanger A (4) Connecting, heat exchanger A (4) fits tightly with the battery cell of set of cells (2), and will flow through heat therein The heat of exchange fluid swaps with the heat of battery cell;Three-way valve A (6) entrance and hydraulic pump A (5) Being connected, an outlet is connected with heating unit A (3), and the case of Battery case (1) is led in another outlet Outer liquid circulating passage footpath;Assignment of traffic unit (7) carries out assignment of traffic to flowing through heat-exchange fluid therein, Assignment of traffic unit (7) entrance is connected with hydraulic pump A (5), and outlet is connected with heat exchanger A (4) Connect;
The outer liquid circulating passage footpath of case include fuel heater (8), switch valve B (9), switch valve C (10), Heat exchanger B (11), switch valve A (12), three-way valve B (13), radiator (14), air conditioning system (20) And fluid reservoir (21);Switch valve B (9) and switch valve C (10) all same with three-way valve A (6) Outlet be connected, switch valve B (9) other end is connected with fuel heater (8), switch valve C (10) another End is connected with heat exchanger B (11);Switch valve A (12) is connected to air conditioning system (20) and heat exchanger Between B (11), constitute the fluid loop of air conditioning system (20);Heat exchanger B (11) is simultaneously and threeway The entrance of valve B (13) connects, and two outlets of three-way valve B (13) connect radiator (14) and liquid respectively Press pump B (16);Switch valve D (22) one end is connected with heating unit A (3), the other end and fluid reservoir (21) It is connected with fuel heater (8);Fluid reservoir (21) connects fuel heater (8), hydraulic pump B (16) respectively With radiator (14);Radiator (14) is configured with fan (15);
It is distributed with temperature in liquid circulating passage footpath and the outer liquid circulating passage footpath of case in Battery case (1), case Sensor;
This system also includes charger (17), realizes coming of heat management system electric energy by electromagnetic switch (18) Source, when charger (17) is connected with electrical network, electromagnetic switch (18) is connected with charger (17), logical Crossing electrical network is that battery thermal management system is powered, when charger (17) is not connected with electrical network, and electromagnetic switch (18) It is connected with set of cells (2), is that battery thermal management system is powered by set of cells (2).
2. according to a kind of Thermal Management System for EV Battery Packs described in claim 1, it is characterised in that Described heat exchanger A (4) is made up of multiple heat exchange modules, the corresponding battery mould of each heat exchange module Block, works alone between each Switching Module, carries out heat management for corresponding battery module.
3. according to a kind of Thermal Management System for EV Battery Packs described in claim 2, it is characterised in that Described assignment of traffic unit (7) is provided with an entrance and multiple outlet, each outlet and heat exchanger A (4) Heat exchange module correspondence connect, the flow of its each outlet is allocated by assignment of traffic unit (7).
4. according to a kind of Thermal Management System for EV Battery Packs described in claim 1, it is characterised in that Described heating unit uses electrical heating.
5. according to the method for work of a kind of Thermal Management System for EV Battery Packs described in claim 1, its Being characterised by, it includes parallel heat management process and battery temperature balance control process;
Wherein, heat management process comprises the following steps:
Step one, judge the ambient temperature of system: preset four temperature thresholds, the temperature of four temperature thresholds Value is followed successively by the second temperature threshold, the first temperature threshold, the 3rd temperature threshold, the 4th temperature threshold from low to high Value, compares with four temperature thresholds in real time by the temperature of set of cells (2);
Step 2, when set of cells (2) temperature less than the first temperature threshold time, need set of cells (2) is entered Row heating:
1) whether first detection electric automobile is in charged state;
1.1) if electric automobile is in charged state:
Enable the first blood circulation: now three-way valve A (6) exports and heating unit A (3) UNICOM, passes through Heat-exchange fluid is heated by heating unit A (3), and drives heat-exchange fluid by hydraulic pump A (5) In battery case inner loop, complete the heating to set of cells (2);
1.2) if electric automobile is not at charged state:
1.2.1) if set of cells (2) temperature is higher than the second temperature threshold, the first blood circulation is started: logical Cross heating unit A (3) heat-exchange fluid is heated, and drive heat exchange flow by hydraulic pump A (5) Body, in battery case inner loop, completes the heating to set of cells (2);
1.2.2) if the temperature of set of cells (2) less than the second temperature threshold, starts the second blood circulation: Now three-way valve A (6) outlet is to switch valve B and switch valve C (10), and switch valve B opens, and opens Closing valve C (10) to close, switch valve D (22) opens, by fuel heater (8) to heat-exchange fluid Heating, heating unit A (3) does not works, and hydraulic pump A (5) driving heat-exchange fluid flows through fuel and adds Hot device (8), through heating heat-exchange fluid during flowing through heat exchanger A (4) to set of cells (2) Heat;
Step 3, when set of cells (2) temperature higher than three temperature thresholds time, set of cells (2) is carried out cold But:
1) if set of cells (2) temperature higher than the 3rd temperature threshold less than the 4th temperature threshold, start the Three blood circulation: three-way valve A (6) outlet UNICOM, to switch valve B (9) and switch valve C (10), and switchs Valve B (9) closes, and switch valve C (10) opens, and switch valve D (22) opens, and three-way valve B (13) enters Mouthful with heat exchanger B (11) UNICOM, three-way valve B (13) outlet UNICOM is to radiator (14), switch valve A (12) close;Hydraulic pump A (5) drives heat-exchange fluid to flow through radiator (14), it is achieved to set of cells (2) Cooling;
2) if set of cells (2) temperature is higher than the 4th temperature threshold, the 4th blood circulation is started: described On the basis of third circulation system, switch valve A (12) is in opening and the refrigeration of air conditioning system (20) Operating mode is opened;Controller controls air conditioning system (20) refrigeration, and switch valve A (12) opens, and cold-producing medium is at sky Heat exchanger B (11) is flowed through under the driving of adjusting system (20);Meanwhile, heat-exchange fluid is in hydraulic pump A (5) Driving under from heat exchanger A (4) flow out, be then passed through radiator (14) and tentatively dispel the heat, then Flow through heat exchanger B (11), and realize heat exchange with the cold-producing medium in air conditioning system (20), thus realize Cooling to set of cells (2).
6. according to the method for work of a kind of Thermal Management System for EV Battery Packs described in claim 5, its It is characterised by, during described heat management, when interior is heated by needs, startup the 5th blood circulation: Three-way valve A (6) is not connected with switch valve B (9) and switch valve C (10), and switch valve A (12), opens Closing valve B, switch valve C (10) all to open, switch valve D (22) closes, and three-way valve B (13) UNICOM is extremely Hydraulic pump B (16);Heat-exchange fluid, under the driving of hydraulic pump B (16), flows through fuel heater (8) And be heated, and then by switch valve B (9) and switch valve C (10) inflow heat exchanger B (11);With Time, air conditioning system (20) drives cold-producing medium through switch valve A (12) inflow heat exchanger B, makes heat exchange Fluid and cold-producing medium realize heat exchange in heat exchanger B (9).
7. according to the method for work of a kind of Thermal Management System for EV Battery Packs described in claim 5, its Being characterised by, described battery temperature balance control process refers to: control unit (19) is each to set of cells (2) The mean temperature of battery module compares with the mean temperature of whole set of cells (2), according to comparative result pair Assignment of traffic unit (7) is controlled, and adjusts the flow of the heat-exchange fluid flowing into each battery module, with reality Show the temperature equalization between each battery module in set of cells (2).
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