Baer Battery Cabinet Patent Series (1989–1997)

Five patents covering the passive cooling and ventilation of battery enclosures — the commercial product that Zomeworks sold to telephone companies (“thousands of units”) and that validated the night-sky radiative cooling principle at scale before the Cool Cell architectural product was developed.

Source files in raw-sources/archives/:

1989-02-21-us4913985-battery-temperature-regulation.pdf
1991-01-22-us5070933-temperature-regulating-system.pdf
1992-12-03-us5316872-passive-cooling-system.pdf
1995-09-11-us5603656-passive-ventilation-device.pdf
1995-07-03-us5660587-passive-ventilation-system.pdf

US 4,913,985 — Battery Temperature Regulation System (1990)

Field	Value
Patent	US 4,913,985
Title	Battery Temperature Regulation System
Inventor	Stephen C. Baer, Albuquerque
Assignee	Zomeworks Corporation, Albuquerque
Filed	Feb 21, 1989
Issued	Apr 3, 1990
Claims	27 Claims, 2 Drawing Sheets
Classification	H01M 10/50 / 429/50; 429/62; 429/120

Abstract: Enclosure for controlling the ambient temperature of a battery using water for heat transfer and thermal mass. Housing with thermally insulated interior defining a cavity that contains the battery. A water container in the cavity in thermal contact with the battery. A flat radiator with nearly horizontal orientation is located above the housing above the level of the water container. Warm supply conduit and cold supply conduit extend from the hollow interior of the radiator to the interior of the water container. Cold supply conduit extends to a position relatively below where the warm supply conduit extends.

Significance: This is the founding patent for the battery cabinet product line. The radiator sits above the water container (not necessarily on the roof); warm water rises through the warm supply conduit to the radiator, cools, and returns through the cold supply conduit — pure thermosiphon, no pump. The water container provides daytime thermal mass to buffer temperature swings. The insulation prevents heat penetration from outside during the day.

This patent is cited as prior art in both US 5,070,933 and US 5,316,872.

US 5,070,933 — Temperature Regulating System (1991)

Field	Value
Patent	US 5,070,933
Title	Temperature Regulating System
Inventor	Stephen C. Baer, Albuquerque
Assignee	Zomeworks Corporation, Albuquerque
Filed	Jan 22, 1991
Issued	Dec 10, 1991
Claims	30 Claims, 2 Drawing Sheets
Classification	F28D 15/00 / 165/104.19; 165/904; 62/467
Prior Baer art	US 4,913,985 (1990)

Abstract: A temperature regulating system including an enclosure with at least one temperature regulator — a container coupled to the ceiling of the enclosure with an upper wall, lower wall, and an intermediate section housing insulation, filled with water. A cooling system independent of external power. The insulation is positioned adjacent to the upper wall of the container; upper surface of the insulation approximately equals the effective heat transfer area of the interior surface of the container. The insulation forms passages for fluid flow between the upper and lower walls. Relatively cold water (chilled by night atmosphere) flows downward from the upper wall through the insulation toward the lower wall, cooling the interior space by heat transfer. Relatively warm water flows upward from the region adjacent to the lower wall, above the insulation, toward the upper wall of the container.

Key refinement over US 4,913,985: The insulation layer inside the container acts as a selective barrier — cold night-cooled water stays stratified at the top, warm room-temperature water at the bottom. This is the insulated ceiling-mounted container concept that directly precedes the Cool Cell ceiling reservoir.

This patent is cited as prior art in the 1995 patent (US 5,513,696) as the immediate predecessor of the corrugated-roof Cool Cell version.

US 5,316,872 — Passive Cooling System (1994)

Field	Value
Patent	US 5,316,872
Title	Passive Cooling System
Inventor	Stephen C. Baer, Albuquerque
Assignee	Zomeworks Corporation, Albuquerque
Filed	Dec 3, 1992
Issued	May 31, 1994
Claims	23 Claims, 3 Drawing Sheets
Classification	H01M 10/50 / 429/62; 429/120; 429/50
Prior Baer art	US 4,913,985 (1990)
Other prior art	Ho-Ming Yeh & Chi-Chien Tseng, “A Thermosyphon Water Cooler With a Parallel, Flat-Plate Radiator,” Energy, vol. 15, No. 12, pp. 1129–1130, 1990

Abstract: Apparatus for controlling the ambient temperature of an enclosure for temperature-sensitive equipment using water. A water container located inside the enclosure. A generally flat, hollow radiator in nearly horizontal configuration proximate and exterior to the enclosure above the level of the upper end of the water container. Exposed upper surface adapted to radiate heat into the atmosphere. A pair of symmetric conduits providing parallel flow paths from spaced-apart container entry/exit positions proximate the upper end of the water container to spaced-apart radiator entry/exit positions in the radiator.

Key refinement: The radiator is now explicitly exterior to the enclosure (on the roof/outside), with symmetric parallel conduits creating balanced thermosiphon flow. The “pair of symmetric conduits” is the two-conduit thermosiphon that appears in the Cool Cell diagrams — warm water up one side, cold water down the other.

The referenced Yeh & Tseng paper from the journal Energy confirms Baer was aware of academic thermosiphon water cooler research.

US 5,603,656 — Passive Ventilation Device and Method (1997)

Field	Value
Patent	US 5,603,656
Title	Passive Ventilation Device and Method
Inventors	Stephen C. Baer AND David C. Harrison, both of Albuquerque
Assignee	Zomeworks Corporation, Albuquerque
Filed	Sep 11, 1995
Issued	Feb 18, 1997
Claims	22 Claims, 1 Drawing Sheet
Classification	H01M 2/12 / 454/339; 424/71

Abstract: Passive ventilation device for releasing hydrogen from an enclosure housing a battery. The enclosure has an outer shell and an inner insulating layer including a gas-permeable panel adjacent one sidewall. The sidewall has an inlet opening and an exhaust opening in communication with a ventilation space to provide upward air flow through the ventilation space to draw hydrogen through the gas-permeable panel into the ventilation space. The upward air flow can be powered by the low density of hydrogen and/or by heating the air within the ventilation space to a temperature greater than the ambient temperature.

Significance: The only co-invented patent with David C. Harrison (Zomeworks VP). The battery cabinet hydrogen venting problem is a real safety issue — charging batteries off-gas hydrogen, which can accumulate in an enclosed cabinet. This passive solution uses the buoyancy of hydrogen itself to drive ventilation — an elegant application of the same natural-convection principles underlying the Cool Cell thermosiphon. Filed the same year as the AU5359096A/US5513696A corrugated-roof patent.

US 5,660,587 — Passive Ventilation System and Method (1997)

Field	Value
Patent	US 5,660,587
Title	Passive Ventilation System and Method
Inventor	Stephen C. Baer, Albuquerque
Assignee	Zomeworks Corporation, Albuquerque
Filed	Jul 3, 1995 (CIP of Ser. No. 275,061, Jul 13, 1994, abandoned)
Issued	Aug 26, 1997
Claims	19 Claims, 3 Drawing Sheets
Classification	F24F 7/00 / 454/237; 429/71

Abstract: Passive ventilation system for venting hydrogen from a battery chamber. Battery chamber with exhaust opening near the upper end and inlet opening. A heat-conductive, gas-impervious conduit extends through the chamber from the inlet. The conduit includes a horizontal portion allowing heat transfer between the interior and exterior of the conduit to equalize the temperature of the gas in the conduit with gas inside the chamber. The incoming fresh air reaches the same temperature as the inside gas before it descends to the lower end — minimizing convective flow in the absence of hydrogen build-up.

Key refinement: The temperature-equalizing conduit prevents normal convection (which would otherwise continuously flush the chamber even without hydrogen). Only hydrogen accumulation (or heating from solar exposure on the conduit wall) drives ventilation. Filed as a continuation-in-part of an abandoned application.

The product lineage

Telephone company battery cabinets → commercial proving ground
US 4,913,985 (1990): flat radiator above water container, thermosiphon
  ↓
US 5,070,933 (1991): insulated ceiling container — stratified cooling
  ↓
US 5,316,872 (1994): outdoor flat radiator with symmetric conduits
  ↓
US 5,513,696 (1995): corrugated-roof version with blow-molded plastic containers
  ↓
US 6,357,512 B1 (2002): Cool Cell — full architectural system
  
Parallel: hydrogen venting patents (1997) for safe battery operation

Zomeworks battery cabinet address

The 1997 patents list Zomeworks at Albuquerque, NM without a specific street address, consistent with the period between the 1984 “1221 Edith NE” address and the 2002 “1011 Sawmill Rd NW” address.