U.S. patent application number 14/925956 was filed with the patent office on 2017-01-05 for heat exchanger for vehicle energy-storage systems.
The applicant listed for this patent is Faraday&Future Inc.. Invention is credited to W. Porter Harris.
Application Number | 20170005305 14/925956 |
Document ID | / |
Family ID | 55085911 |
Filed Date | 2017-01-05 |
United States Patent
Application |
20170005305 |
Kind Code |
A1 |
Harris; W. Porter |
January 5, 2017 |
Heat Exchanger For Vehicle Energy-Storage Systems
Abstract
Provided are cooling subsystems for a vehicle energy-storage
system comprising a heat exchanger disposed between two battery
modules. The heat exchanger can be thermally coupled to each of a
plurality of cells of the battery modules at an end of each cell
and fluidly coupled to a coolant system, the heat exchanger
transferring heat from the plurality of cells.
Inventors: |
Harris; W. Porter; (Los
Angeles, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Faraday&Future Inc. |
Gardena |
CA |
US |
|
|
Family ID: |
55085911 |
Appl. No.: |
14/925956 |
Filed: |
October 28, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14866882 |
Sep 26, 2015 |
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14925956 |
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62186977 |
Jun 30, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01M 10/6569 20150401;
H01M 2/1083 20130101; H01M 10/625 20150401; H01M 10/613 20150401;
H01M 2220/20 20130101; Y02E 60/10 20130101; H01M 10/6557 20150401;
H01M 2/1077 20130101; H01M 10/6567 20150401 |
International
Class: |
H01M 2/10 20060101
H01M002/10; H01M 10/6557 20060101 H01M010/6557; H01M 10/613
20060101 H01M010/613 |
Claims
1. A vehicle energy-storage system comprising: a plurality of
modules, each module including: two half modules coupled together,
each half module including: a plurality of cells, the cells being
cylindrical rechargeable lithium-ion cells each having a first end
and a second end, the first end distal from the second end, and
having an anode terminal and a cathode terminal being disposed at
the first end; and an enclosure having the cells disposed therein,
the enclosure including a power connector electrically coupled to
the plurality of cells; a main power connector electrically coupled
to the power connectors of the two half modules; and a heat
exchanger disposed between the two half modules, the heat exchanger
being thermally coupled to each of the plurality of cells of the
two half modules at the second end, the heat exchanger being
fluidly coupled to a coolant system, the heat exchanger
transferring heat from the plurality of cells; a tray having the
plurality of modules disposed therein, the tray including: a
positive bus bar; a negative bus bar, the positive and negative bus
bars being separately electrically coupled to the main power
connector associated with each of the plurality of modules; and the
coolant system for circulating coolant being pumped into the tray
such that each of the modules is at approximately the same
predetermined temperature.
2. The energy-storage system of claim 1 wherein the heat exchanger
comprises at least one of: aluminum, copper, and an aluminum-copper
alloy.
3. The energy-storage system of claim 2 wherein an exterior surface
of the heat exchanger comprises at least one of: aluminum oxide,
diamond powder based materials, and boron nitride.
4. The energy-storage system of claim 3 wherein the coolant
comprises at least one of: synthetic oil, water and ethylene glycol
(WEG), poly-alpha-olefin oil, and liquid dielectric cooling based
on phase change.
5. The energy-storage system of claim 1 wherein the heat exchanger
comprises aluminum, an exterior surface of the heat exchanger
comprises aluminum oxide, and the coolant comprises WEG.
6. The energy-storage system of claim 1 wherein each half module
further includes a current carrier electrically coupled to the
cells, the cathode terminal of each of the cells being coupled to a
respective positive contact of the current carrier, and the anode
terminal of each of the cells being coupled to a respective
negative contact of the current carrier.
7. The energy-storage system of claim 6 wherein the cathode
terminal of each cell is laser welded to the respective positive
contact of the current carrier and the anode terminal of each cell
is laser welded to the respective negative contact of the current
carrier.
8. The energy-storage system of claim 6 wherein the current carrier
includes a plurality of fuses each electrically coupled to the
respective positive contact.
9. The energy-storage system of claim 1 wherein the tray is sized
and arranged to be disposed in the chassis of an electric vehicle,
at least two adjacent modules of the plurality of modules are
fluidly and electrically coupled to each other, and the cells are
oriented and mounted horizontally in each half module.
10. The energy-storage system of claim 1 wherein the cells are
oriented and mounted horizontally in each half module and the
modules are arranged in six rows with each row consisting of six
modules.
11. The energy storage system of claim 1 wherein each half module
is 70 mm-100 mm wide and the heat exchanger is 2 mm-30 mm wide, and
each half module and the heat exchanger are each 250 mm-400 mm
long.
12. A vehicle energy-storage system comprising: a plurality of
modules, at least two adjacent modules of the plurality of modules
being fluidly and electrically coupled to each other, each module
comprising: two half modules coupled together, each half module
including: a plurality of cells, the cells being oriented
horizontally, the cells being cylindrical rechargeable lithium-ion
cells each having a first end and a second end, the first end
distal from the second end, and having an anode terminal and a
cathode terminal being disposed at the first end; a current carrier
electrically coupled to the cells, the cathode terminal of each of
the cells being coupled to a respective positive contact of the
current carrier, the anode terminal of each of the cells being
coupled to a respective negative contact of the current carrier;
and an enclosure having the cells and the current carrier disposed
therein, the enclosure including a power connector electrically
coupled to the plurality of cells; a main power connector
electrically coupled to the power connectors of the two half
modules; and a heat exchanger disposed between the two half
modules, the heat exchanger being thermally coupled to each of the
plurality of cells of the two half modules at the second end, the
heat exchanger being fluidly coupled to a coolant system, the heat
exchanger transferring heat from the plurality of cells; a tray
having the plurality of modules disposed therein, the tray
including: a positive bus bar; and a negative bus bar, the positive
and negative bus bars being separately electrically coupled to the
main power connector associated with each of the plurality of
modules; and the coolant system for circulating coolant being
pumped into the tray such that each of the modules is at
approximately the same predetermined temperature.
13. The cooling subsystem of claim 18 wherein the heat exchanger
comprises at least one of aluminum, copper, and an aluminum-copper
alloy, and an exterior surface of the heat exchanger comprises at
least one of aluminum oxide, diamond powder based materials, and
boron nitride.
14. The cooling subsystem of claim 19 wherein the coolant comprises
at least one of: synthetic oil, water and ethylene glycol (WEG),
poly-alpha-olefin oil, and liquid dielectric cooling based on phase
change.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/866,882 filed Sep. 26, 2015, which claims
the benefit of U.S. Provisional Application No. 62/186,977 filed on
Jun. 30, 2015. This application is related to U.S. patent
application Ser. No. 14/841,617 filed on Aug. 31, 2015. The subject
matter of the aforementioned applications is incorporated herein by
reference for all purposes.
FIELD
[0002] The present application relates generally to heat transfer,
and more specifically to heat transfer for vehicle energy-storage
systems.
BACKGROUND
[0003] It should not be assumed that any of the approaches
described in this section qualify as prior art merely by virtue of
their inclusion in this section.
[0004] Electric-drive vehicles offer a solution for reducing the
impact of fossil-fuel engines on the environment and transforming
automotive mobility into a sustainable mode of transportation.
Energy-storage systems are essential for electric-drive vehicles,
such as hybrid electric vehicles, plug-in hybrid electric vehicles,
and all-electric vehicles. However, present energy-storage systems
have disadvantages including large size, inefficiency, and poor
safety, to name a few. Similar to many sophisticated electrical
systems, heat in automotive energy-storage systems should be
carefully managed. Current thermal management schemes consume an
inordinate amount of space. Present energy-storage systems also
suffer from inefficiencies arising variously from imbalance among
battery cells and resistance in various electrical connections. In
addition, current energy-storage systems are not adequately
protected from forces such as crash forces encountered during a
collision.
SUMMARY
[0005] This summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the Detailed Description. This summary is not intended to identify
key features or essential features of the claimed subject matter,
nor is it intended to be used as an aid in determining the scope of
the claimed subject matter.
[0006] According to various embodiments, the present disclosure may
be directed to cooling subsystem for a vehicle comprising: a heat
exchanger disposed between two battery modules, the heat exchanger
being thermally coupled to each of a plurality of cells of the
battery modules at an end of each cell, the heat exchanger being
fluidly coupled to a coolant system, the heat exchanger
transferring heat from the plurality of cells.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Embodiments are illustrated by way of example and not
limitation in the figures of the accompanying drawings, in which
like references indicate similar elements.
[0008] FIG. 1 illustrates an example environment in which an
energy-storage system can be used.
[0009] FIG. 2A shows an orientation of battery modules in an
energy-storage system, according to various embodiments of the
present disclosure.
[0010] FIG. 2B depicts a bottom part of an enclosure of a partial
battery pack such as shown in FIG. 2A.
[0011] FIG. 3 is a simplified diagram illustrating coolant flows,
according to example embodiments.
[0012] FIG. 4 is a simplified diagram of a battery module,
according to various embodiments of the present disclosure.
[0013] FIG. 5 illustrates a half module, in accordance with various
embodiments.
[0014] FIGS. 6A and 6B show a current carrier, according to various
embodiments.
[0015] FIG. 7 depicts an example battery cell.
[0016] FIGS. 8A and 8B illustrate further embodiments of a battery
module.
DETAILED DESCRIPTION
[0017] While this disclosure is susceptible of embodiment in many
different forms, there are shown in the drawings and will herein be
described in detail several specific embodiments with the
understanding that the present disclosure is to be considered as an
exemplification of the principles of the disclosure and is not
intended to limit the disclosure to the embodiments illustrated.
The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the disclosure. As used herein, the singular forms "a," "an," and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises," "comprising," "includes," and
"including," when used in this specification, specify the presence
of stated features, integers, steps, operations, elements, and/or
components, but do not preclude the presence or addition of one or
more other features, integers, steps, operations, elements,
components, and/or groups thereof. It will be understood that like
or analogous elements and/or components, referred to herein, may be
identified throughout the drawings with like reference characters.
It will be further understood that several of the figures are
merely schematic representations of the present disclosure. As
such, some of the components may have been distorted from their
actual scale for pictorial clarity.
[0018] Some embodiments of the present invention can be deployed in
a wheeled, self-powered motor vehicle used for transportation, such
as hybrid electric vehicles, plug-in hybrid electric vehicles, and
all-electric vehicles. For example, FIG. 1 illustrates electric car
100. Electric car 100 can be an automobile propelled by one or more
electric motors 110. Electric motor 110 can be coupled to one or
more wheels 120 through a drivetrain (not shown in FIG. 1).
Electric car 100 can include frame 130 (also known as an underbody
or chassis). Frame 130 can be a supporting structure of electric
car 100 to which other components can be attached/mounted, such as,
for example, a battery pack 140a. Battery pack 140a can supply
electricity to power one or more electric motors 110, for example,
through an inverter. The inverter can change direct current (DC)
from battery pack 140a to alternating current (AC), as can be
required for electric motors 110, according to some
embodiments.
[0019] As depicted in FIG. 1, battery pack 140a may have a compact
"footprint" and be at least partially enclosed by frame 130 and
disposed to provide a predefined separation, for example, from
structural rails 150 of an upper body that couples to frame 130.
Accordingly, at least one of rear crumple zone 160, front crumple
zone 170, and lateral crumple zone 180 can be formed around battery
pack 140a. Both the frame 130 and structural rails 150 may protect
battery pack 140a from forces or impacts exerted from outside of
electric car 100, for example, in a collision. In contrast, other
battery packs which extend past at least one of structural rails
150, rear crumple zone 160, and front crumple zone 170 remain
vulnerable to damage and may even explode in an impact.
[0020] Battery pack 140a may have a compact "footprint" such that
it may be flexibly used in and disposed on frame 130 having
different dimensions. Battery pack 140a can also be disposed in
frame 130 to help improve directional stability (e.g., yaw
acceleration). For example, battery pack 140a can be disposed in
frame 130 such that a center of gravity of electric car 100 is in
front of the center of the wheelbase (e.g., bounded by a plurality
of wheels 120).
[0021] FIG. 2A shows battery pack 140b with imaginary x-, y-, and
z-axis superimposed, according to various embodiments. Battery pack
140b can include a plurality of battery modules 210. In a
non-limiting example, battery pack 140b can be approximately 1000
mm wide (along x-axis), 1798 mm long (along y-axis), and 152 mm
high (along z-axis), and can include thirty-six of battery modules
210.
[0022] FIG. 2B illustrates exemplary enclosure 200 for battery pack
140b having a cover removed for illustrative purposes. Enclosure
200 includes a tray 260 and a plurality of battery modules 210.
Tray 260 may include positive bus bar 220 and negative bus bar 230.
Positive bus bar 220 can be electrically coupled to a positive (+)
portion of a power connector of each battery module 210. Negative
bus bar 230 can be electrically coupled to a negative (-) portion
of a power connector of each battery module 210. Positive bus bar
220 can be electrically coupled to positive terminal 240 of
enclosure 200. Negative bus bar 230 can be electrically coupled to
negative terminal 250 of enclosure 200. As described above with
reference to FIG. 1, because bus bars 220 and 230 can be within
structural rails 150, they can be protected from collision
damage.
[0023] According to some embodiments, negative bus bar 230 and
positive bus bar 220 can be disposed along opposite edges of tray
260 to provide a predefined separation between negative bus bar 230
and positive bus bar 220. Such separation between negative bus bar
230 and positive bus bar 220 can prevent or at least reduce the
possibility of a short circuit (e.g., of battery pack 140b) due to
a deformity caused by an impact.
[0024] As will be described further in more detail with reference
to FIG. 5, battery module 210 can include at least one battery cell
(details not shown in FIG. 2A, see FIG. 7). The at least one
battery cell can include an anode terminal, a cathode terminal, and
a cylindrical body. The battery cell can be disposed in each of
battery module 210 such that a surface of the anode terminal and a
surface of the cathode terminal are normal to the imaginary x-axis
referenced in FIG. 2A (e.g., the cylindrical body of the battery
cell is parallel to the imaginary x-axis). This can be referred to
as an x-axis cell orientation.
[0025] In the event of fire and/or explosion in one or more of
battery modules 210, the battery cells can be vented along the
x-axis, advantageously minimizing a danger and/or a harm to a
driver, passenger, cargo, and the like, which may be disposed in
electric car 100 above battery pack 140b (e.g., along the z-axis),
in various embodiments.
[0026] The x-axis cell orientation of battery modules 210 in
battery pack 140b shown in FIGS. 2A and 2B can be advantageous for
efficient electrical and fluidic routing to each of battery module
210 in battery pack 140b. For example, at least some of battery
modules 210 can be electrically connected in a series (forming
string 212), and two or more of string 212 can be electrically
connected in parallel. This way, in the event one of string 212
fails, others of string 212 may not be affected, according to
various embodiments.
[0027] FIG. 3 illustrates coolant flows and operation of a coolant
system and a coolant sub-system according to various embodiments.
As shown in FIG. 3, the x-axis cell orientation can be advantageous
for routing coolant (cooling fluid) in parallel to each of battery
modules 210 in battery pack 140b. Coolant can be pumped into
battery pack 140b at ingress 310 and pumped out of battery pack
140b at egress 320. A resulting pressure gradient within battery
pack 140b can provide sufficient circulation of coolant to minimize
a temperature gradient within battery pack 140b (e.g., a
temperature gradient within one of battery modules 210, a
temperature gradient between battery modules 210, and/or a
temperature gradient between two or more of strings 212 shown in
FIG. 2A).
[0028] Within battery pack 140b, the coolant system may circulate
the coolant, for example, to battery modules 210 (e.g., the
circulation is indicated by reference numeral 330). One or more
additional pumps (not shown in FIG. 3) can be used to maintain a
roughly constant pressure between multiple battery modules 210
connected in series (e.g., in string 212 in FIG. 2A) and between
two or more of string 212. Within each battery module 210, the
coolant sub-system may circulate the coolant, for example, between
and within two half modules 410 and 420 shown in FIG. 4 (e.g., the
circulation indicated by reference numeral 340).
[0029] In some embodiments, the coolant can enter each battery
module 210 through interface 350 between two half modules 410 and
420, in a direction (e.g., along the y- or z-axis) perpendicular to
the cylindrical body of each battery cell, and flow to each cell.
Driven by pressure within the coolant system, the coolant then can
flow along the cylindrical body of each battery (e.g., along the
x-axis) and may be collected at two (opposite) side surfaces 360A
and 360B of the module that can be normal to the x-axis. In this
way, heat can be efficiently managed/dissipated and thermal
gradients minimized among all battery cells in battery pack 140b,
such that a temperature may be maintained at an approximately
uniform level.
[0030] In some embodiments, parallel cooling, as illustrated in
FIG. 3, can maintain temperature among battery cells in battery
pack 140b at an approximately uniform level such that a direct
current internal resistance (DCIR) of each battery cell can be
maintained at an substantially predefined resistance. The DCIR can
vary with a temperature, therefore, keeping each battery cell in
battery pack 140b at a substantially uniform and predefined
temperature can result in each battery cell having substantially
the same DCIR. Since a voltage across each battery cell can be
reduced as a function of its respective DCIR, each battery cell in
battery pack 140b may experience substantially the same loss in
voltage. In this way, each battery cell in battery pack 140b can be
maintained at approximately the same capacity and imbalances
between battery cells in battery pack 140b can be minimized,
improving battery efficiency.
[0031] In some embodiments, when compared to techniques using metal
tubes to circulate coolant, parallel cooling can enable higher
battery cell density within battery module 210 and higher battery
module density in battery pack 140b. In some embodiments, coolant
or cooling fluid may be at least one of the following: synthetic
oil, for example, poly-alpha-olefin (or poly-.alpha.-olefin, also
abbreviated as PAO) oil, ethylene glycol and water, liquid
dielectric cooling based on phase change, and the like.
[0032] FIG. 4 illustrates battery module 210 according to various
embodiments. Main power connector 460 can provide power from
battery cells 450 to outside of battery module 210. Coolant can be
provided to battery module 210 at main coolant input port 480,
receive/transfer heat from battery module 210, and be received at
main coolant output port 470. In some embodiments, battery module
210 can include two half modules 410 and 420, each having
respective enclosure 430. Enclosure 430 may be made using one or
more plastics having sufficiently low thermal conductivities.
Respective enclosures 430 of each of two half modules 410 and 420
may be coupled with each other to form the housing for battery
module 210.
[0033] FIG. 4 includes view 440 of enclosure 430 (e.g., with a
cover removed). For each of half modules 410, 420 there is shown a
plurality of battery cells 450 oriented (mounted) horizontally (see
also FIGS. 5 and 8A). By way of non-limiting example, each half
module can include one hundred four of battery cells 450. By way of
further non-limiting example, eight of battery cells 450 can be
electrically connected in a series (e.g., the staggered column of
eight battery cells 450 shown in FIG. 4), with a total of thirteen
of such groups of eight battery cells 450 electrically connected in
series. By way of additional non-limiting example, the thirteen
groups (e.g., staggered columns of eight battery cells 450
electrically coupled in series) can be electrically connected in
parallel. This example configuration may be referred to as "8S13P"
(8 series, 13 parallel). In some embodiments, the 8S13P electrical
connectivity can be provided by current carrier 510, described
further below in relation to FIGS. 5 and 6. Other combinations and
permutations of battery cells 450 electrically coupled in series
and/or parallel may be used.
[0034] FIG. 5 depicts a view of half modules 410, 420 without
enclosure 430 in accordance with various embodiments. Half modules
410 and 420 need not be the same, for example, they may be mirror
images of each other in some embodiments. Half modules 410 and 420
can include a plurality of battery cells 450. The plurality of
battery cells 450 can be disposed between current carrier 510 and
blast plate 520 such that an exterior side of each of battery cells
450 is not in contact with the exterior sides of other (e.g.,
adjacent) battery cells 450. In this way, coolant can circulate
among and between battery cells 450 to provide submerged, evenly
distributed cooling. In addition, to save the weight associated
with coolant in areas where cooling is not needed, air pockets can
be formed using channels craftily designed in space 530 between
current carrier 510 and blast plate 520 not occupied by battery
cells 450.
[0035] Coolant can enter half modules 410, 420 through coolant
intake 540, be optionally directed by one or more flow channels,
circulate among and between the plurality of battery cells 450, and
exits through coolant outtake 550. In some embodiments, coolant
intake 540 and coolant outtake 550 can each be male or female fluid
fittings. In some embodiments, coolant or cooling fluid is at least
one of: synthetic oil such as poly-alpha-olefin (or
poly-.alpha.-olefin, abbreviated as PAO) oil, ethylene glycol and
water, liquid dielectric cooling based on phase change, and the
like. Compared to techniques using metal tubes to circulate
coolant, submerged cooling improves a packing density of battery
cells 450 (e.g., inside battery module 210 and half modules 410,
420) by 15%, in various embodiments.
[0036] FIGS. 6A and 6B depict current carrier 510, 510A according
to various embodiments. Current carrier 510, 510A can be generally
flat (or planar) and can comprise one or more layers (not shown in
FIGS. 6A and 6B), such as a base layer, a positive power plane, a
negative power plane, and signal plane sandwiched in-between
dielectric isolation layers (e.g., made of polyimide). In some
embodiments, the signal plane can include signal traces and be used
to provide battery module telemetry (e.g., battery cell voltage,
current, state of charge, and temperature from optional sensors on
current carrier 510) to outside of battery module 210.
[0037] As depicted in FIG. 6B, current carrier 510A can be a
magnified view of a portion of current carrier 510, for
illustrative purposes. Current carrier 510A can be communicatively
coupled to each of battery cells 450, for example, at separate
(fused) positive (+) portion 630 and separate negative (-) portion
640 which may be electrically coupled to the positive power plane
and negative power plane (respectively) of current carrier 510A,
and to each cathode and anode (respectively) of battery cell 450.
In some embodiments, positive (+) portion 630 can be laser welded
to a cathode terminal of battery cell 450, and negative (-) portion
640 can be laser welded to an anode terminal of battery cell 450.
In some embodiments, the laser-welded connection can have on the
order of 5 milli-Ohms resistance. In contrast, electrically
coupling the elements using ultrasonic bonding of aluminum bond
wires can have on the order of 10 milli-Ohms resistance. Laser
welding advantageously can have lower resistance for greater power
efficiency and take less time to perform than ultrasonic wire
bonding, which can contribute to greater performance and
manufacturing efficiency.
[0038] Current carrier 510A can include fuse 650 formed from part
of a metal layer (e.g., copper, aluminum, etc.) of current carrier
510A, such as in the positive power plane. In some embodiments,
fuse 650 can be formed (e.g., laser etched) in a metal layer (e.g.,
positive power plane) to dimensions corresponding to a type of
low-resistance resistor and acts as a sacrificial device to provide
overcurrent protection. For example, in the event of thermal
runaway of one of battery cell 450 (e.g., due to an internal short
circuit), the fuse may "blow," breaking the electrical connection
to battery cell 450 and electrically isolating battery cell 450
from current carrier 510A. Although an example of a fuse formed in
the positive power plane was provided, a fuse may additionally or
alternatively be a part of the negative power plane.
[0039] Additional thermal runaway control can be provided in
various embodiments by scoring on end 740 (identified in FIG. 7) of
battery cell 450. The scoring can promote rupturing to effect
venting in the event of over pressure. In various embodiments, all
battery cells 450 may be oriented to allow venting into blast plate
520 for both half modules.
[0040] In some embodiments, current carrier 510 can be comprised of
a printed circuit board and a flexible printed circuit. For
example, the printed circuit board may variously comprise at least
one of copper, FR-2 (phenolic cotton paper), FR-3 (cotton paper and
epoxy), FR-4 (woven glass and epoxy), FR-5 (woven glass and epoxy),
FR-6 (matte glass and polyester), G-10 (woven glass and epoxy),
CEM-1 (cotton paper and epoxy), CEM-2 (cotton paper and epoxy),
CEM-3 (non-woven glass and epoxy), CEM-4 (woven glass and epoxy),
and CEM-5 (woven glass and polyester). By way of further
non-limiting example, the flexible printed circuit may comprise at
least one of copper foil and a flexible polymer film, such as
polyester (PET), polyimide (PI), polyethylene naphthalate (PEN),
polyetherimide (PEI), along with various fluoropolymers (FEP), and
copolymers.
[0041] In addition to electrically coupling battery cells 450 to
each other (e.g., in series and/or parallel), current carrier 510
can provide electrical connectivity to outside of battery module
210, for example, through main power connector 460 (FIG. 4).
Current carrier 510 may also include electrical interface 560
(FIGS. 5, 6A) which transports signals from the signal plane.
Electrical interface 560 can include an electrical connector (not
shown in FIG. 5, 6a).
[0042] FIG. 7 shows battery cell 450 according to some embodiments.
In some embodiments, battery cell 450 can be a lithium ion (li-ion)
battery. For example, battery cell 450 may be an 18650 type li-ion
battery having a cylindrical shape with an approximate diameter of
18.6 mm and approximate length of 65.2 mm. Other rechargeable
battery form factors and chemistries can additionally or
alternatively be used. In various embodiments, battery cell 450 may
include can 720 (e.g., the cylindrical body), anode terminal 770,
and cathode terminal 780. For example, anode terminal 770 can be a
negative terminal of battery cell 450 and cathode terminal 780 can
be a positive terminal of battery cell 450. Anode terminal 770 and
cathode terminal 780 can be electrically isolated from each other
by an insulator or dielectric.
[0043] FIG. 8A illustrates an apparatus for heat exchange in
battery module 210a, according to various embodiments. Battery
module 210a can comprise two half modules 410 and 420, and heat
exchanger 810 disposed between two half modules 410 and 420. Each
of two half modules 410, 420 can comprise battery cells 450, as
described in relation to FIG. 4. Main power connector 460 (as
described in relation to FIG. 4) can be represented by male main
power connector 460.sub.M, optional main power connector openings
460.sub.P (e.g., associated with half module 410, half module 420
(not depicted in FIG. 8A), and heat exchanger 810), and female main
power connector 460.sub.F. In some embodiments, optional main power
connector opening 460.sub.P (e.g., of heat exchanger 810) can be an
electrical connector coupled to at least one electrical connector
of half modules 410 and 420 (e.g., an associated main power
connector opening 460.sub.P). Main coolant input port 480 (as
described in relation to FIG. 4) can be represented by female main
coolant input port 480.sub.F; male main coolant input port (e.g.,
associated with half modules 410) and main coolant intakes (e.g.,
associated with heat exchanger 810) are not depicted in FIG. 8A.
Main coolant output port 470 (as described in relation to FIG. 4)
can be represented by male main coolant output port 470.sub.M, main
coolant outtakes 470.sub.O, and female main coolant output port
470.sub.F. Each of female main power connector 460.sub.F, female
main cooling input 480.sub.F, and female main cooling output
470.sub.F can include an (rubber) o-ring or other seal. Other
combinations and permutations of male and female connectors--such
as a mix of male and female connectors on each side, and female
connectors on the right side and male connectors on the left
side--may be used. In some embodiments, battery module 210a does
not include blast plate 420 (FIG. 4).
[0044] Half modules 410 and 420 may include a plurality of battery
cells 450 which may be oriented (mounted) horizontally. By way of
non-limiting example, each half module can include one hundred four
of battery cells 450. By way of further non-limiting example, eight
of battery cells 450 can be electrically connected in a series
(e.g., the staggered column of eight battery cells 450), with a
total of thirteen of such groups of eight battery cells 450
electrically connected in series. By way of additional non-limiting
example, the thirteen groups (e.g., staggered columns of eight
battery cells 450 electrically coupled in series) may be
electrically connected in parallel. This example configuration may
be referred to as "8S13P" (8 series, 13 parallel). Other
combinations and permutations of battery cells 450 electrically
coupled in series and/or parallel may be used. For example, more or
less than one hundred and four of battery cells may be included in
each half module, depending on the power, capacity, and size of the
battery cells. As another example, more or less than thirteen
groups of battery cells may be electrically connected in
parallel.
[0045] According to some embodiments, battery module 210a can
include heat exchanger 810. Heat exchanger 810 can comprise two
side surfaces 820 which can be thermally coupled to battery cells
450 (of at least one of two half modules 410 and 420), for example,
at end 740 (FIG. 7). In various embodiments, side surfaces 820 can
(also) be mechanically coupled to end 740 of battery cells 450 (of
at least one of two half modules 410 and 420), for example, using a
thermal adhesive or glue (e.g., thermally conductive two-part epoxy
resin). In some embodiments, heat exchanger 810 can be thermally
coupled and electrically isolated from battery cells 450 (of at
least one of two half modules 410 and 420) using dielectric
separation having (extremely) low electrical conductivity. For
example, an exterior surface of heat exchanger 810 (including side
surfaces 420) can comprise at least one of: aluminum oxide, diamond
powder based materials, boron nitride, and the like.
[0046] Heat exchanger 810 can comprise at least one of aluminum,
copper, an alloy of aluminum and copper, and the like. In some
embodiments, heat exchanger 810 may comprise aluminum. Heat
exchanger 810 can transfer heat from battery cells 450 (of at least
one of two half modules 410 and 420). In operation, heat exchanger
810 may receive heat from battery cells 450 and transfer the heat
to another medium, such as coolant or cooling fluid. For example,
the coolant can enter heat exchanger 810 (e.g., from the coolant
system and/or sub-system) through a main coolant intake (not shown
in FIG. 8A) and exit heat exchanger 810 (e.g., to the coolant
system and/or sub-system) from main coolant outtake 4700. An
interior of heat exchanger 810 (not shown in FIG. 8A) may comprise
a plurality of channels to circulate the coolant inside heat
exchanger 810 to efficiently transfer heat from battery cells 450
(of at least one of two half modules 410 and 420) to the coolant.
For example, the plurality of channels can direct the coolant from
the main coolant intake, circulate the coolant inside heat
exchanger 810, and direct the coolant to main coolant outtake
4700.
[0047] The coolant may be at least one of the following: synthetic
oil, water and ethylene glycol (WEG), poly-alpha-olefin (or
poly-a-olefin, also abbreviated as PAO) oil, liquid dielectric
cooling based on phase change, and the like. In various
embodiments, the coolant can comprise WEG. By way of further
non-limiting example, the coolant may be at least one of:
perfluorohexane (Flutec PP1), perfluoromethylcyclohexane (Flutec
PP2), Perfluoro-1,3-dimethylcyclohexane (Flutec PP3),
perfluorodecalin (Flutec PP6), perfluoromethyldecalin (Flutec PP9),
trichlorofluoromethane (Freon 11), trichlorotrifluoroethane (Freon
113), methanol (methyl alcohol 283-403K), ethanol (ethyl alcohol
273-403K), and the like.
[0048] As described in relation to FIG. 3, the coolant system may
evenly circulate coolant through each heat exchanger 810 in a
plurality of battery modules 210/210a.
[0049] FIG. 8B shows some example constituent components--half
module 410, heat exchanger 810, and half module 420--assembled into
battery module 210a, according to various embodiments. In some
embodiments, half modules 410 and 420 can each have width 890
within a range of 70 mm-100 mm, and heat exchanger 810 has width
880 within a range of 2 mm-30 mm. In various embodiments, half
modules 410 and 420 and heat exchanger 810 can have length 885 in a
range of 250 mm-400 mm.
[0050] As would be readily appreciated by one of ordinary skill in
the art, various embodiments described herein may be used in
additional applications, such as in energy-storage systems for wind
and solar power generation. Other applications are also
possible.
[0051] The description of the present disclosure has been presented
for purposes of illustration and description, but is not intended
to be exhaustive or limited to the invention in the form disclosed.
Many modifications and variations will be apparent to those of
ordinary skill in the art without departing from the scope and
spirit of the invention. Exemplary embodiments were chosen and
described in order to best explain the principles of the present
disclosure and its practical application, and to enable others of
ordinary skill in the art to understand the invention for various
embodiments with various modifications as are suited to the
particular use contemplated.
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