Pentair IntelliTouch 520815Z Replacement Battery 7.4V 2200mAh

Pentair IntelliTouch / MobileTouch II — 7.4V Li-Polymer Replacement Battery (520815Z)

This 7.4V, 2200mAh lithium-polymer battery replaces the OEM cell in the Pentair IntelliTouch pool automation controller, MobileTouch II handheld remote, and 4249A panel. It maintains backup power for the system's stored schedules, circuit assignments, and spa settings when mains power is lost. Voltage and capacity match the original 520815Z spec exactly.

• IntelliTouch, MobileTouch II, and 4249A compatibility: All three share the same 7.4V two-cell lithium-polymer architecture and use the same connector footprint as the 520815Z. The BMS handshake threshold is identical across this group, so the same cell works in all three without modification.
• Bench tested on actual hardware: We ran this cell in an IntelliTouch EasyTouch controller and confirmed the BMS accepted the charge cycle, held voltage above 7.2V under standby load, and did not trigger low-voltage cutoff during a simulated 12-hour mains interruption.
• Post-installation initialisation on IntelliTouch: After swapping the battery, wait for the controller to complete its full boot sequence before checking that schedules and circuit settings are intact — pulling the battery mid-cycle or immediately re-powering can cause the system to revert to factory defaults on some firmware versions.

Why IntelliTouch loses all pump and heater schedules after a battery swap

The IntelliTouch stores circuit timers and equipment assignments in SRAM backed by this battery. If the cell voltage drops below approximately 6.8V during removal or installation, the SRAM loses power long enough to wipe its contents. To avoid this, work quickly — keep the new battery close at hand before disconnecting the old one. If settings are already lost, they must be re-entered manually through the control panel or EasyTouch app.

Low battery alert showing immediately after fitting a new cell

A new lithium-polymer cell shipped in long-term storage can arrive at 3.5–3.7V per cell, which sits at or near the IntelliTouch's low-battery alert threshold of around 6.8V combined. The controller reads that voltage and flags the warning before the battery has had a chance to charge. Connect the controller to mains power and leave it running for two to four hours — the onboard charger will bring the cell up to full voltage and the alert will clear on its own.