Why your smart meter never needs a new battery?

You Can't Specify a Smart-Meter Battery Like an Ordinary One

Start with a real device profile: an NB-IoT smart gas meter draws only a few microamps while idle—orders of magnitude below a phone on standby. But it wakes up several times a day, and the instantaneous peak current during a transmission burst can reach several hundred milliamps, even over 1 amp. The moment it finishes, it drops straight back to microamp-level sleep.

This "long-term microamp sleep, instantaneous milliamp pulse" power profile places three almost contradictory demands on the battery:

First, self-discharge must be low enough. A meter battery sits untouched for ten years. If it quietly lost 5% of its charge every year, half the capacity would be gone by year ten. Forte's Li-SOCl₂ batteries show an annual self-discharge rate of ≤1%, with a room-temperature shelf life exceeding 10 years.

Second, the voltage plateau must be stable enough. The MCU and RF module inside the device typically need a steady voltage above 3.0V to operate correctly. If the battery voltage keeps sagging as capacity drops, the device can "shut down" while charge still remains. Forte's Li-SOCl₂ discharge curve is exceptionally flat—over 90% of capacity is delivered on a nearly constant high-voltage plateau.

Third, pulse capability must be strong enough. This is the most overlooked—and most failure-prone—requirement. Li-SOCl₂ offers very high energy density, but its nature is: high energy, limited burst. If the device's transmission peak exceeds the battery's pulse rating, the voltage collapses instantly, causing communication failure or even a device reset. Forte's ER26500 supports a maximum pulse of 300 mA; the ER34615 reaches even higher pulse output. When your device's peak exceeds that, a combined solution is required.

From a Single Cell to a System: What ER+FPC Solves

Forte's answer is to pair the Li-SOCl₂ cell with an FPC (battery capacitor). The principle is simple: the capacitor handles the "burst," the battery handles the "endurance." While the device sleeps, the battery trickle-charges the capacitor at microamp levels. When a transmission is needed, the capacitor releases a high current instantly, covering the battery's pulse gap. A single capacitor charge can support multiple communication pulses without the battery ever facing the surge directly.

In practice, this solution resolves a classic engineering pain point. Forte's ER+FPC capacitor solution delivers long-life, stable, highly reliable power for IoT, smart metering, and oil & gas exploration. In NB-IoT and LoRa devices, the hybrid improves both reliability and service life in hard-to-reach, remotely installed equipment.

Which Devices Especially Need the Hybrid?

Smart gas meters: NB-IoT and LoRa modules draw high transmit currents, and pulse capability drops further in low temperatures—the hybrid safeguards communication success rates.

Smart water meters: installed in stairwells and manholes where battery replacement is extremely costly, demanding both long life and pulse reliability.

Asset trackers: GPS fixes draw large instantaneous currents, and devices are dispersed and hard to service.

Industrial sensors: wide temperature swings impose a dual test of wide-temperature tolerance and pulse performance.

Forte's Product Line Is Essentially a "Scenario Matching Table"

Forte doesn't sell a "universal battery." We match the solution to the scenario.

Why Forte

Forte Battery has specialized in primary lithium batteries for 26 years. We are a National High-Tech Enterprise and a provincial-level "Little Giant" (Specialized, Sophisticated, Differentiated, Innovative) firm, holding more than 40 national patents. Our products are certified to UL, CE, UN38.3 and explosion-proof standards, among others.

In 2025, the company invested RMB 170 million in the Xiaogan Linkong Industrial Park, expected to commence production by the end of 2026. Annual capacity will rise from 10 million to 46 million cells, continuing to supply safe, reliable battery products to IoT, smart metering and smart-city applications worldwide.