Battery and battery-sensing apparatuses and methods
Apparatuses and methods for determining one or more performance related characteristics (such as state of charge and/or health) of one or more electrochemical cells that store and release electrical energy are disclosed. Embodiments include pressure and/or temperature sensors that sense a change in pressure resulting from the tendency of the electrochemical cell to change volume and/or the temperature of the one or more electrochemical cells as the electrochemical cell(s) are charged or discharged. Alternate embodiments include one or more calculating members that receive pressure and/or temperature information from the pressure and/or temperature sensing members and calculate a performance related characteristic of the electrochemical cell. Still further embodiments include determining one or more performance related characteristics of an electrochemical cell by sensing the tendency of an electrochemical cell to change volume (such as by sensing pressure) and/or by sensing the temperature as the electrochemical cell is charged or discharged.
1. An apparatus for detecting damage to a rechargeable battery, comprising:
a pressure sensing member configured and adapted to sense a two dimensional pressure distribution on a surface of a rechargeable battery, the pressure sensing member including a plurality of pressure sensors, each said pressure sensor configured and adapted to sense a corresponding localized surface expansion or contraction of the battery and provide a signal;
a computer having software that receives the plurality of signals from the pressure sensing member, the software using the heterogeneity of the signals to identify damage to the battery.
2. The apparatus of claim 1 , wherein the plurality of pressure sensors are arranged in a 3-dimensional array.
3. The apparatus of claim 1 , wherein the software calculates localized pressure gradients of the battery using the received plurality of signals.
4. The apparatus of claim 1 , wherein the software calculates a pressure distribution of the battery using the received plurality of signals.
5. The apparatus of claim 4 , wherein the software calculates one or more pressure distributions of the battery using the received plurality of signals, the one or more pressure distributions being selected from the group consisting of a 2D pressure distribution, a 3D pressure distribution, and a 2D and a 3D pressure distribution.
6. The apparatus of claim 1 , wherein the software uses statistical calculations of the received pressure information to identify damage to the battery.
7. The apparatus of claim 6 , wherein the statistical calculations include the standard deviation of the plurality of signals.
8. The apparatus of claim 1 , wherein the software receives the plurality of signals from the battery while the battery is at different states of charge.
9. The apparatus of claim 8 , wherein the software compares the plurality of signals from the battery at different states of charge.
10. The apparatus of claim 1 , wherein the pressure sensing member is positioned adjacent an external surface of the battery.
11. The apparatus of claim 1 , wherein the battery is positioned at least partially within an external housing, and the pressure sensing member is in contact with an external surface of the external housing.
12. The apparatus of claim 11 , wherein the external housing allows expansion of the battery, and wherein the pressure sensing member is held against an external surface with a support member that resists expansion.
13. The apparatus of claim 1 , wherein the battery is positioned at least partially within an external housing, and the pressure sensing member is positioned within the interior of the external housing.
14. The apparatus of claim 1 , wherein the pressure sensing member is configured and adapted to sense a change in pressure resulting from the tendency of the battery to change volume as the battery is charged or discharged.
15. The apparatus of claim 1 wherein the battery is a Lithium-ion battery.
16. The apparatus of claim 15 wherein the expansion or contraction of the battery results from intercalation of Li ions.
17. The apparatus of claim 16 wherein the software receives a first plurality of signals when the battery is charged to a first voltage, a second plurality of signals when the battery is charged to a second voltage different than the first voltage, and the software uses the difference in heterogeneity of the first plurality compared to the heterogeneity of the second plurality to identify damage.
18. The apparatus of claim 1 wherein the software receives a first plurality of signals when the battery is charged to a first voltage, a second plurality of signals when the battery is charged to a second voltage different than the first voltage, and the software uses the difference in heterogeneity of the first plurality compared to the heterogeneity of the second plurality to identify damage.