Vehicle energy-storage systems having parallel cooling

1. An energy-storage system having parallel cooling comprising:

a plurality of modules in a battery pack, each module including:

a plurality of cells, the cells being cylindrical rechargeable cells, the cells being oriented and mounted parallel to a horizontal axis in each module;

a current carrier electrically coupled to the cells, a cathode terminal of each of the cells being coupled to a respective first contact of the current carrier, an anode terminal of each of the cells being coupled to a respective second contact of the current carrier;

a plate disposed substantially parallel to the current carrier such that the cells are disposed between the current carrier and the plate; and

an enclosure having the cells, the current carrier, and the plate disposed therein, the enclosure comprising a coolant sub-system for circulating liquid coolant flowing into the enclosure through a coolant input port and out of the enclosure through a coolant output port, the cells being disposed between the current carrier and the plate such that an exterior side of each of the cells is not in contact with the exterior sides of other cells, the coolant sub-system circulating liquid coolant in parallel among and between the cells to provide submerged, distributed cooling such that each of the cells is at approximately the same predetermined temperature;

a tray having the plurality of modules disposed therein; and

a coolant system for circulating liquid coolant flowing into the tray across the plurality of modules in parallel such that each of the modules is at approximately the same predetermined temperature,

wherein the coolant sub-system of each module receives the liquid coolant from the coolant system at an intermediate location within the module and circulates the liquid coolant along two opposing directions parallel to the horizontal axis to distribute the coolant among and between the cells.

2. The energy-storage system of claim 1 , wherein the coolant system creates a pressure gradient for liquid coolant flowing into the battery pack and out of the battery pack, the pressure gradient within the battery pack providing circulation of the liquid coolant so as to minimize a temperature gradient within the battery pack.

3. The energy-storage system of claim 1 , wherein the cells are disposed between the current carrier and the plate such that an exterior side of each of the cells is not in contact with the exterior sides of other cells, the coolant sub-system circulating liquid coolant among and between the cells to provide submerged, substantially even distributed cooling.

4. The energy-storage system of claim 1 , wherein air pockets are formed using channels in a space between the current carrier and the plate that is not occupied by the cells, the air pockets comprising a fluid other than the liquid coolant.

5. The energy-storage system of claim 4 , wherein the liquid coolant flows through each module along a cylindrical body of a battery cell within the module.

6. The energy-storage system of claim 1 , wherein the modules are arranged in a plurality of strings, each string of the plurality of strings including a plurality of modules.

7. The energy-storage system of claim 6 , wherein the liquid coolant flows through the plurality of strings in parallel and the liquid coolant flows within each string of the plurality of strings in parallel.

8. The energy-storage system of claim 1 , wherein the liquid coolant comprises at least one of a synthetic oil, ethylene glycol and water, and a liquid dielectric.

9. The energy-storage system of claim 1 , wherein at least two adjacent modules of the plurality of modules are fluidly and electrically coupled to each other.

10. A container of an energy-storage system having parallel cooling comprising:

a plurality of module housings, each module comprising two half module housings coupled together, each half module housing is configured to receive a plurality of cylindrical cells mounted parallel to a horizontal axis, each cell having an anode terminal and a cathode terminal being disposed at one end, the half module housing further including:

a current carrier electrically coupled to the cells, the cathode terminal of each of the cells being coupled to a respective first contact of the current carrier, the anode terminal of each of the cells being coupled to a respective second contact of the current carrier; the current carrier including a plurality of fuses each electrically coupled to the respective first contact;

a retainer element disposed substantially parallel to the current carrier and configured to mount the cells horizontally within each half module housing; and

an enclosure having the current carrier and the retainer element disposed therein;

a tray having the plurality of module housings 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 power connectors associated with the plurality of module housings; and

a coolant system for circulating liquid coolant flowing into the tray across the plurality of module housings and battery cells in parallel such that each of the module housings and each of the cells is at approximately the same predetermined temperature,

wherein the enclosure further comprises a coolant sub-system which provides submerged, distributed cooling to the cells by receiving the liquid coolant from the coolant system at an intermediate location between the two half module housings and circulating the liquid coolant along two opposing directions parallel to the horizontal axis to distribute the coolant among and between the cells.