The utility model content
The utility model aims to provide a kind of bipolar plates, coldplate and fuel cell pack that effectively reduces the temperature difference of fuel single battery center and marginal position.
To achieve these goals; An aspect according to the utility model provides a kind of bipolar plates, has coolant flow field on the side of bipolar plates; Coolant flow field comprises: the coolant entrance passage has the coolant entrance of the upstream extremity that is positioned at coolant flow field; The coolant outlet passage, the coolant outlet with the downstream that is positioned at coolant flow field; Many runner ditches spaced apart and runner ridge; Runner ditch and runner ridge extend between coolant entrance passage and coolant outlet passage concurrently; Wherein, On the bearing of trend of coolant entrance passage, the area and/or the girth in the cross section of the runner ditch in the middle of being positioned in many runner ditches are maximum, and reduce gradually at area and/or the girth towards the cross section of the direction upper runner ditch of both sides.
Further, the area in the cross section of runner ditch is reduced to reducing gradually of noncontinuity gradually.
Further, the degree of depth of each runner ditch equates that all the width of the runner ditch in the middle of being positioned at is maximum, and reduces gradually at the width towards the direction upper runner ditch of both sides.
Further, the width of each runner ditch equates that all the degree of depth of the runner ditch in the middle of being positioned at is maximum, and reduces gradually in the degree of depth towards the direction upper runner ditch of both sides.
Further, each runner ridge section area equates.
Further, coolant entrance and coolant outlet are one, and coolant entrance and coolant outlet are respectively near the position at two diagonal angles of bipolar plates; Perhaps, coolant entrance is two, and coolant outlet is one, and two coolant entrances lay respectively at two ends of coolant entrance passage, and coolant outlet is positioned at the middle part of coolant outlet passage.
Further; The surface configuration of runner ditch is the rough surface with roughness of setting; And; On the bearing of trend of coolant entrance passage, the roughness of the rough surface of the runner ditch in the middle of being positioned in many runner ditches is maximum, and reduces gradually in the roughness towards the rough surface of the direction upper runner ditch of both sides.
Further, the coolant outlet channel parallel is in the coolant entrance passage, and runner ditch and runner ridge are all perpendicular to coolant entrance passage and coolant outlet passage.
Another aspect according to the utility model also provides a kind of coldplate, has coolant flow field at least one side of coldplate, and coolant flow field comprises: the coolant entrance passage has the coolant entrance of the upstream extremity that is positioned at coolant flow field; The coolant outlet passage, the coolant outlet with the downstream that is positioned at coolant flow field; Many runner ditches spaced apart and runner ridge; Runner ditch and runner ridge extend between coolant entrance passage and coolant outlet passage concurrently; Wherein, On the bearing of trend of coolant entrance passage, the area and/or the girth in the cross section of the runner ditch in the middle of being positioned in many runner ditches are maximum, and reduce gradually at area and/or the girth towards the cross section of the direction upper runner ditch of both sides.
Further, the area in the cross section of runner ditch is reduced to reducing gradually of noncontinuity gradually.
Further, the degree of depth of each runner ditch equates that all the width of the runner ditch in the middle of being positioned at is maximum, and reduces gradually at the width towards the direction upper runner ditch of both sides.
Further, the width of each runner ditch equates that all the degree of depth of the runner ditch in the middle of being positioned at is maximum, and reduces gradually in the degree of depth towards the direction upper runner ditch of both sides.
Further, each runner ridge section area equates.
Further, coolant entrance and coolant outlet are one, and coolant entrance and coolant outlet are respectively near the position at two diagonal angles of coldplate; Perhaps, coolant entrance is two, and coolant outlet is one, and two coolant entrances lay respectively at two ends of coolant entrance passage, and coolant outlet is positioned at the middle part of coolant outlet passage.
Further; The surface configuration of runner ditch is the rough surface with roughness of setting; And; On the bearing of trend of coolant entrance passage, the roughness of the rough surface of the runner ditch in the middle of being positioned in many runner ditches is maximum, and reduces gradually in the roughness towards the rough surface of the direction upper runner ditch of both sides.
Further, the coolant outlet channel parallel is in the coolant entrance passage, and runner ditch and runner ridge are all perpendicular to coolant entrance passage and coolant outlet passage.
Another aspect according to the utility model; A kind of fuel cell pack also is provided; Comprise a plurality of stacked inferior battery pile; Each inferior battery pile includes a plurality of bipolar plates and is arranged on the membrane electrode assembly between two adjacent bipolar plates, has coldplate between two adjacent inferior battery pile, and coldplate is above-mentioned coldplate.
Use the technical scheme of the utility model; Have coolant flow field on the side of bipolar plates or at least one side of coldplate, this coolant flow field comprises: coolant entrance passage, coolant outlet passage, many runner ditches spaced apart and runner ridge; Wherein, the coolant entrance passage has the coolant entrance of the upstream extremity that is positioned at coolant flow field; The coolant outlet passage has the coolant outlet of the downstream that is positioned at coolant flow field; Runner ditch and runner ridge extend between coolant entrance passage and coolant outlet passage concurrently; Wherein, On the bearing of trend of coolant entrance passage; The area and/or the girth in the cross section of the runner ditch in the middle of being positioned in many runner ditches are maximum, and reduce gradually at area and/or the girth towards the cross section of the direction upper runner ditch of both sides.In the above-mentioned coolant flow field, increased the coolant rate or the heat exchange area of single battery center effectively, the center that makes cooling effect be not so good as the edge is cooled off faster, and then makes the Temperature Distribution of each single battery more even.
Embodiment
Need to prove that under the situation of not conflicting, embodiment and the characteristic among the embodiment among the application can make up each other.Below with reference to accompanying drawing and combine embodiment to specify the utility model.
As shown in Figure 1, have coolant flow field on the side of the bipolar plates of embodiment one, this coolant flow field comprises: coolant entrance passage 121, coolant outlet passage 122, many runner ditches 123 spaced apart and runner ridge 124.Wherein, coolant entrance passage 121 has the coolant entrance of the upstream extremity that is positioned at coolant flow field; Coolant outlet passage 122 has the coolant outlet of the downstream that is positioned at coolant flow field, and many runner ditches 123 spaced apart and runner ridge 124 extend between coolant entrance passage 121 and coolant outlet passage 122 concurrently; Preferred embodiment the most a kind of, coolant outlet passage 122 is parallel to coolant entrance passage 121, and runner ditch 123 and runner ridge 124 are all perpendicular to coolant entrance passage 121.
On the bearing of trend of coolant entrance passage 121, the area and/or the girth in the cross section of the runner ditch 123 in the middle of being positioned in many runner ditches 123 are maximum, and reduce gradually at area and/or the girth towards the cross section of the direction upper runner ditch 123 of both sides.In the coolant flow field of the bipolar plates of embodiment one; The coolant rate or the heat exchange area of single battery center have been increased effectively; The center that makes cooling effect be not so good as the edge is cooled off faster, and then makes the Temperature Distribution of each single battery of fuel cell pack more even.
The area in the cross section of runner ditch 123 is reduced to reducing gradually of continuity or noncontinuity (ladder property) gradually.A kind of preferred embodiment in, the degree of depth of each runner ditch 123 equates that all the width of the runner ditch 123 in the middle of being positioned at is maximum, and reduces gradually at the width towards the direction upper runner ditch 123 of both sides.In another preferred embodiment, the width of each runner ditch 123 equates that all the degree of depth of the runner ditch 123 in the middle of being positioned at is maximum, and reduces gradually in the degree of depth towards the direction upper runner ditch 123 of both sides.As shown in Figure 1, each runner ridge 124 area of section equates.
As shown in Figure 1, coolant entrance passage 121 has a coolant entrance, and coolant outlet passage 122 has a coolant outlet, and coolant entrance and coolant outlet are respectively near the position at two diagonal angles of bipolar plates 12.
As shown in Figure 2; In embodiment two; For the flow velocity of the cooling agent of accelerating the center, coolant entrance passage 121 has two coolant entrances, and coolant outlet passage 122 has a coolant outlet; Two coolant entrances lay respectively at two ends of coolant entrance passage 121, and coolant outlet is positioned at the middle part of coolant outlet passage 122.
Preferably; The surface of runner ditch 123 (being the bottom surface of runner ditch 123 and/or the relative side of adjacent fluid channels ridge 124) is the rough surface with roughness of setting; And; On the bearing of trend of coolant entrance passage 121, the roughness of the rough surface of the runner ditch 123 in the middle of being positioned in many runner ditches 123 is maximum, and reduces gradually in the roughness towards the rough surface of the direction upper runner ditch 123 of both sides.As preferred embodiment a kind of, adopt coarse runner wall in the position that the heat radiation of the center of the single battery of fuel cell pack is slow, adopt smooth runner wall in the position that the thermal diffusion of fuel cell edge is fast.In the heat transfer process that no phase transformation takes place, the runner wall that roughness is big can promote the convection current of boundary layer fluid to mix, and improves heat exchange rate.Simultaneously, the runner wall that roughness is big helps increasing heat exchange area.In the heat transfer process that gas-liquid phase transition takes place, the runner inner surface that roughness is big can promote the forming core of cenotype, accelerates the suction exothermic process of phase transformation, improves heat exchange rate.
The variation tendency of roughness comprises but is not limited to the variation pattern of successional variation pattern and noncontinuity (ladder property).Said method may cause runner ditch internal pressure loss to increase, and reduces the flow of cooling fluid in the runner ditch, and actual cooling effect is relevant with roughness.
The method of change runner roughness comprises but is not limited to adopt the method for hot investment casting or machining being processed to form groove on the bottom surface of runner ditch 123 and/or on the relative side of adjacent fluid channels ridge 124.And change on the bottom surface of runner ditch 123 through the density degree that changes groove and/or the roughness on the relative side of adjacent fluid channels ridge 124.Generally, on the bearing of trend of coolant entrance passage 121, the groove pitch of the runner ditch 123 in the middle of being positioned at is minimum, and increases gradually in the spacing towards the groove of the direction upper runner ditch of both sides.
As shown in Figure 3, the fuel cell pack of embodiment one comprises a plurality of stacked inferior battery pile 18 and the end plate 11 that is arranged on 18 two ends of a plurality of inferior battery pile, and each inferior battery pile 18 can be made up of a single battery; Comprise two bipolar plates and be arranged on a membrane electrode assembly between two bipolar plates, perhaps, inferior battery pile 18 also can be made up of a plurality of single batteries; Such as; In embodiment one, as shown in Figure 4, each inferior battery pile 18 includes two single batteries; Particularly; Comprise three bipolar plates 12 and two membrane electrode assemblies 15, membrane electrode assembly 15 is arranged between two adjacent bipolar plates 12, and positive pole and negative reaction gas flow 13 are arranged between two adjacent bipolar plates 12; At least one bipolar plates is above-mentioned bipolar plates in two bipolar plates 12 that are in contact with one another in two adjacent inferior battery pile 18; Promptly can only have on the bipolar plates 12 and have coolant flow field, also can be all to have coolant flow field 17 on two bipolar plates 12, and this coolant flow field 17 is arranged on the side of membrane electrode assembly dorsad 15 of bipolar plates 12.Also be provided with sealing ring 14 between bipolar plates 12 and the bipolar plates 12 and between bipolar plates 12 and the membrane electrode assembly 15.
As shown in Figure 4, have coolant flow field at least one side of the coldplate of embodiment one, this coolant flow field comprises: coolant entrance passage 161, coolant outlet passage 162, many runner ditches 163 spaced apart and runner ridge 164.Wherein, coolant outlet passage 162 is parallel to coolant entrance passage 161; Many runner ditch spaced apart 163 all is provided with perpendicular to coolant entrance passage 161 with runner ridge 164; Wherein, On the bearing of trend of coolant entrance passage 161; The area in the cross section of the runner ditch 163 in the middle of being positioned in many runner ditches 163/or girth is maximum, and towards the area in the cross section of the direction upper runner ditch 163 of both sides/or girth reduce gradually.The difference of the embodiment of present embodiment and above-mentioned bipolar plates is that coolant flow field no longer is arranged on the bipolar plates 12, and is arranged on the coldplate 16.The technical scheme and the effect of present embodiment are similar to the aforementioned embodiment, repeat no more at this.
The area in the cross section of runner ditch 163 is reduced to reducing gradually of continuity or noncontinuity (ladder property) gradually.A kind of preferred embodiment in, the degree of depth of each runner ditch 163 equates that all the width of the runner ditch 163 in the middle of being positioned at is maximum, and reduces gradually at the width towards the direction upper runner ditch 163 of both sides.In another preferred embodiment, the width of each runner ditch 163 equates that all the degree of depth of the runner ditch 163 in the middle of being positioned at is maximum, and reduces gradually in the degree of depth towards the direction upper runner ditch 163 of both sides.As shown in Figure 4, each runner ridge 164 area of section equates.
As shown in Figure 4, the coolant entrance passage 161 of the coldplate of embodiment one has a coolant entrance, and coolant outlet passage 162 has a coolant outlet.Coolant entrance and coolant outlet are respectively near the position at two diagonal angles of coldplate 16.
As shown in Figure 5, for the flow velocity of the cooling agent of accelerating the center, the coolant entrance passage 161 of the coldplate of embodiment two has two coolant entrances, and coolant outlet passage 162 has a coolant outlet.Two coolant entrances lay respectively at two ends of coolant entrance passage 161, and coolant outlet is positioned at the middle part of coolant outlet passage 162.
Preferably; The surface of runner ditch 163 is the rough surface with roughness of setting; And; On the bearing of trend of coolant entrance passage 161, the roughness of the rough surface of the runner ditch 163 in the middle of being positioned in many runner ditches 163 is maximum, and reduces gradually in the roughness towards the rough surface of the direction upper runner ditch 163 of both sides.
As preferred embodiment a kind of, adopt coarse runner wall in the position that the heat radiation of the center of the single battery of fuel cell pack is slow, adopt smooth runner wall in the position that the thermal diffusion of fuel cell edge is fast.In the heat transfer process that no phase transformation takes place, the runner wall that roughness is big can promote the convection current of boundary layer fluid to mix, and improves heat exchange rate.Simultaneously, the runner wall that roughness is big helps increasing heat exchange area.In the heat transfer process that gas-liquid phase transition takes place, the runner inner surface that roughness is big can promote the forming core of cenotype, accelerates the suction exothermic process of phase transformation, improves heat exchange rate.
The variation tendency of roughness comprises but is not limited to the variation pattern of successional variation pattern and noncontinuity (ladder property).Said method may cause runner ditch internal pressure loss to increase, and reduces the flow of cooling fluid in the runner ditch, and actual cooling effect is relevant with roughness.
The method of change runner roughness comprises but is not limited to adopt the method for hot investment casting or machining being processed to form groove on the bottom surface of runner ditch 163 and/or on the relative side of adjacent fluid channels ridge 164.And change on the bottom surface of runner ditch 163 through the density degree that changes groove and/or the roughness on the relative side of adjacent fluid channels ridge 164.Generally, on the bearing of trend of coolant entrance passage 161, the groove pitch of the runner ditch 163 in the middle of being positioned at is minimum, and increases gradually in the spacing towards the groove of the direction upper runner ditch of both sides.
As shown in Figure 6; The fuel cell pack of embodiment two comprises a plurality of stacked inferior battery pile 18; In the present embodiment, each inferior battery pile 18 includes two single batteries, is provided with coldplate 16 between two adjacent inferior battery pile 18; This coldplate 16 is above-mentioned coldplate, has coolant flow field 19 at least one side of coldplate 16.
In conjunction with referring to Fig. 7 and Fig. 8; Fig. 7 shows cooling agent and gets into coldplate 16 through feed tube, flows out from drain pipe, wherein again; Feed tube comprises the feed liquor person in charge 50 and a plurality of feed liquor arms 52 that are connected with the feed liquor person in charge 50, and drain pipe comprises the fluid arm 53 that the fluid person in charge 51 connects.In Fig. 8, fuel cell pack 1 is connected to heat exchanger 2, coolant delivery pump 3 and register 4 respectively through circulation line 5.Wherein, air cooling blower fan 6 is used for cold wind to heat exchanger 2 being provided.Fuel cell pack 1 can be any fuel battery pile that can produce power, like proton membrane fuel battery heap or DMFC heap etc.
Heat exchanger 2 can select for use air or water as the cold junction medium, and as in certain embodiments, the cold junction medium can be dry air or humid air.And in other embodiments, the cold junction medium can be the water or the aqueous solution.The type of cooling of heat exchanger can adopt water-water cooling or water-air cooling but, also can adopt water-water-water cooling or water-water-air cooling but.Register 4 is used to regulate the temperature of the coolant that gets into fuel cell; Mainly comprise temperature sensor, control element and executive component; Wherein temperature sensor can be but be not limited to thermocouple; Control element can be for having electronic system or the special control system of the cooling of integrated platform and fuel cell, and executive component comprises cooling element and heating element or one of them.
The coolant that is used for fuel cell pack can be the fluid that can carry heat of any kind, and as in certain embodiments, fluid cooling media can be the combination of pure water or water and additive.And in other embodiments, fluid cooling media can be a liquid metal, for example, and based on the low-melting alloy of gallium indium.In certain embodiments, fluid cooling media experiences gas-liquid phase transition when heat exchange, and in other embodiments, fluid cooling media does not undergo phase transition.
The preferred embodiment that the above is merely the utility model is not limited to the utility model, and for a person skilled in the art, the utility model can have various changes and variation.All within the spirit and principle of the utility model, any modification of being done, be equal to replacement, improvement etc., all should be included within the protection range of the utility model.