HYBRID VEHICLE WITH A LOW VOLTAGE SOLAR PANEL CHARGING A HIGH VOLTAGE BATTERY USING A SERIES CHARGER TO SEPARATELY CHARGE INDIVIDUAL CELLS OF THE SERIES CONNECTED BATTERY

• US 20080143292A1
• Filed: 02/19/2008
• Published: 06/19/2008
• Est. Priority Date: 08/24/2005
• Status: Active Grant

• Current Assignee: Thomas A. Ward
• Original Assignee: Thomas A. Ward
• Inventors: Ward, Thomas A.
• Granted Patent: US 7,884,569 B2
• Time in Patent Office: Days
• US Class Current: 320/101
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/12 Buck converters
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2250/10 by alarm
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 8/003 Converting light into electric energy, e.g. by using photo-voltaic systems
• CPC Class Codes: H02J 2310/44 for aircrafts
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y10S 903/907 Electricity storage, e.g. battery, capacitor

Abstract

A series charger (80) is provided to charge a high voltage battery (42) in an electric vehicle with a low voltage solar panel (50). The series charger (80) provides switches (84₁, 84₂) to connect the terminals of solar panel (50) across individual battery cells (34_1-n) in series connected battery (42) one battery cell at a time. Charging by series charger (80) can occur while the cells (34_1-n) of battery (42) remain connected in series. With the series charger (80), the high voltage battery (42) can be charged by the low voltage solar panel (50) without using a lossy DC-DC converter. The high voltage battery (42) charged by series charger (80) can be connected in parallel with a second high voltage battery to enable charging all cells of the second battery together. The solar panel (50) can be provided in a moon roof or truck bed cover adjustable to track the sun.

Claims

1. A solar battery charging system for a vehicle comprising:

an electric motor;

a battery connected to the electric motor, the battery comprising a plurality of series connected battery cells;

a solar panel having an output voltage lower than the voltage of the battery; and

a series charger comprising;

switches that selectively connect terminals of the solar panel in parallel with each of the series connected battery cells; and

a switch controller configured to control the switches to separately connect the solar panel in parallel with each of the series battery cells, one of the battery cells at a time, while the series battery cells, including the battery cell connected in parallel with the solar panel, remain connected in series.

2. The solar battery charging system of claim 1,

wherein the switches further include switches that selectively connect and disconnect the battery cells in series, and

wherein the switch controller is further configured to control the switches to connect the solar panel in parallel with at least one of the series battery cells while controlling the switches to disconnect at least one of the series battery cells.

3. The solar battery charging system of claim 2, wherein the switch controller is configured to disconnect all the series battery cells concurrently, while concurrently connecting the solar panel in parallel with all of the series battery cells.

4. The solar battery charging system of claim 1, wherein the battery comprises:

a first battery connected to the electric motor; and

a second battery comprising the series connected battery cells connectable by the series charger to the solar panel, wherein the first battery is connected in parallel with the second battery.

5. The solar battery charging system of claim 1, further comprising:

at least one of a truck bed cover and a moon roof supporting the solar panel; and

a tilt angle adjustment mechanism attached to the at least one of the truck bed cover and the moon roof, and

a controller connected to the tilt angle adjustment mechanism, the controller configured to adjust the tilt angle adjustment mechanism to an angle determined from a sensor so that the solar panel is directed toward the sun to provide substantially a maximum charge output.

6. The solar battery charging system of claim 1, wherein the solar panel is attached to a truck bed cover.

7. The solar battery charging system of claim 1, wherein the battery comprises a plurality of battery packs connected in parallel, wherein at least one of the battery packs is attached to the truck bed cover.

8. The solar battery charging system of claim 1, further comprising:

an AC plug in power source connection; and

an AC-DC converter connecting the AC plug in power source connection to the series charger, the AC-DC converter further connecting to the switches of the series charger so that the output of the AC-DC converter is connected to connections for the solar panel to provide charge to the battery cells, one of the cells at a time.

9. The solar battery charging system of claim 1, wherein the solar panel further includes a connection for connecting directly to a low voltage electrical system of the vehicle to directly power components in the low voltage electrical system.

10. The solar battery charging system of claim 1, wherein the battery cells each comprise individual batteries connected in series.

11. The solar battery charging system of claim 1, wherein the switches comprise one or more of tri-state buffers, relays, and transistor pass gates.

12. The solar battery charging system of claim 1, wherein the series charger further comprises:

a timer, wherein the controller is connected to the timer, the solar controller configured to cause the switches to connect the solar panel to different ones of the battery cells at predetermined time intervals measured using the timer.

13. The solar battery charging system of claim 1, wherein the series charger further comprises:

a battery charge monitor, wherein the controller is connected to the battery charge monitor, the solar controller programmed to cause the switches to connect the solar panel to different ones of the battery cells at a predetermined charge level as measured from the battery charge monitor.

19. The solar battery charging system of claim 1, wherein the battery comprises a plurality of battery packs connected in parallel, wherein at least one of the battery packs is attached to the truck bed cover.

14. A solar battery charging system for a vehicle comprising:

an electric motor;

a battery connected to the electric motor, the battery comprising a plurality of series connected battery cells;

a solar panel having an output voltage lower than the voltage of the battery; and

a series charger comprising;

switches that selectively connect terminals of the solar panel in parallel with each of the series connected battery cells and that selectively connect and disconnect the battery cells in series, and

a switch controller configured to control the switches to connect the solar panel in parallel with at least one of the series battery cells while controlling the switches to disconnect at least one of the series battery cells.

15. The solar battery charging system of claim 14, wherein the switch controller is configured to disconnect all the series battery cells concurrently, while concurrently connecting the solar panel in parallel with all of the series battery cells.

16. The solar battery charging system of claim 14, wherein the battery comprises:

a first battery connected to the electric motor; and

a second battery comprising the series connected battery cells connectable by the series charger to the solar panel, wherein the first battery is connected in parallel with the second battery.

17. The solar battery charging system of claim 14, further comprising:

at least one of a truck bed cover and a moon roof supporting the solar panel; and

a tilt angle adjustment mechanism attached to the at least one of the truck bed cover and the moon roof, and

a controller connected to the tilt angle adjustment mechanism, the controller configured to adjust the tilt angle adjustment mechanism to an angle determined from a sensor so that the solar panel is directed toward the sun to provide substantially a maximum charge output.

18. The solar battery charging system of claim 14, wherein the solar panel is attached to a truck bed cover.