Filonator Cell

The Filonator was presented at the September 1927 National Radio Exhibition in London as a revolutionary advance over accumulators. It was patented and positioned as a safe, convenient home-maintained power supply. In practice, like other chemical “tablet-recharge” systems of the period, it was a consumable primary battery disguised as rechargeable, relying on the renewal of fresh zinc and electrolyte. This limited its commercial life, as it could not match the true reusability of secondary lead-acid accumulators once consumer experience caught up with the marketing claims.

Technical Description

• Cell Type: Two-fluid primary cell (non-accumulator).
• Electrodes:
  • Anode: Zinc, contained within a porous pot.
  • Cathode: Encircling carbon plate forming the other electrode surface.
• Voltage & Capacity:
  • Nominal Voltage: Likely around 1.5 volts per cell, as this was standard for zinc-carbon chemistry cells.
  • Capacity: Not explicitly documented, but expected to be suitable for several weeks of average domestic radio use (the tablet charge lasting approximately six weeks). This implies a relatively modest capacity, sufficient to power low-current vacuum tube filaments.
• Electrolyte System:
  • Activated by dissolving specially prepared compressed tablets in tap water to prepare two separate solutions.
  • The use of tablets allowed the user to effectively “recharge” the cell at home, though functionally the cell was not rechargeable in electrochemical terms; instead, it was replenished with fresh electrolyte and a new zinc element.
• Case: Self-contained unit in a moulded casing adapted for use in radio receivers.
• Operating Principle:
  • During discharge, zinc is consumed in a redox reaction with the cell’s electrolyte, while the carbon electrode acts as the cathodic surface.
  • At the end of a cycle, the zinc electrode was replaced and the electrolyte refreshed via the tablets.
  • This process gave the impression of an “instant recharge,” although it was strictly a renewably fueled primary cell.

Claimed Advantages

• No use of sulphuric acid, fumes, or risk of spillage (unlike conventional lead-acid accumulators).
• Remarkably simple user-maintenance — recharge accomplished at home with tablets and water, without visiting an accumulator charging station.
• Each tablet-based “charge” was advertised to last around six weeks under average radio-use conditions.
• Intended as standard equipment in General Radio Company receivers, replacing the traditional accumulator for filament supply.

Manufacturer

In mid-1927, General Radio Co. Ltd. obtained exclusive manufacturing and sales rights for the Filonator, a novel battery technology licensed from Darimont Electric Batteries Ltd.

Vous pourrez trouver sous ce lien 18 modèles d'appareils, 12 avec des images et 0 avec des schémas.
Tous les appareils de General Radio Co. Ltd.; London