HNN9008 Replacement Battery – 7.5V Power for Motorola GP328

PTM-328 Ni-MH Battery for Motorola GP/HT/PRO/MTX Series Radios

The PTM-328 is a professional-grade nickel-metal hydride battery engineered to meet the demanding requirements of Motorola's GP, HT, PRO, and MTX series portable radios. Operating at 7.5V with capacity options of 1800mAh and 2000mAh, it delivers consistent performance across a wide range of communication applications. Designed to meet original HNN9008 specifications, it maintains full compatibility with models including GP320/328/338, HT750/1250/1550, PRO5150/7150/9150, and MTX850/950/8250.

The PTM-328 provides exceptional voltage stability and extended cycle life, ensuring reliable operation in various environmental conditions. The battery's robust construction and optimized power management make it suitable for professional use where dependable communication is essential. 

The PTM-328 is a direct replacement energy solution designed to revitalize legacy Motorola radio fleets. Engineered to match the exact physical and electrical specifications of the OEM HNN9008 battery, this unit operates at a stable 7.5V. It is available in 1800mAh or 2000mAh capacities, providing a significant runtime upgrade over aging standard nickel-cadmium packs. The battery housing is constructed from high-impact ABS polycarbonate, ultrasonically welded to ensure seal integrity and shock resistance, making it suitable for rugged industrial handling.

Compatibility is the core strength of this two-way radio battery. It is fully compatible with a broad spectrum of Motorola's professional series, including the GP328, GP338, HT1250, PRO5150, and MTX850. The internal cells utilize proven Nickel-Metal Hydride (Ni-MH) chemistry, which offers higher energy density than Ni-Cd without the strict shipping regulations associated with Li-Ion. This makes the PTM-328 an ideal choice for organizations looking to extend the service life of their existing communication infrastructure without investing in entirely new radio systems.

Key Advantages

Extended Shift Runtime
Standard duty cycles in public safety and industrial sectors require radios to transmit and receive for 8 to 12 hours. Aging OEM batteries often fail to hold a charge past the 6-hour mark, creating dangerous communication gaps. The PTM-328 features high-grade Ni-MH cells with capacity options up to 2000mAh. This increased energy density ensures that even with frequent high-power transmission, your Motorola GP328 or HT750 remains operational throughout a full shift. By reducing the need for mid-shift battery swaps, you improve workforce efficiency and eliminate the logistical headache of carrying spare batteries in the field.

Precision Mechanical Fit
Aftermarket batteries often suffer from poor housing tolerances, leading to loose connections or difficulty latching onto the radio chassis. The PTM-328 is manufactured using precision molds that strictly adhere to the HNN9008 form factor. This ensures a tight, secure mechanical lock with the radio body, preventing power loss due to vibration or drops. Furthermore, the gold-plated external contacts are positioned to align perfectly with standard Motorola desktop chargers and multi-unit gang chargers. You do not need to purchase proprietary chargers; this replacement battery integrates seamlessly into your existing charging infrastructure.

Stable Ni-MH Chemistry
While Lithium batteries are popular, many legacy Motorola chargers are designed specifically for Nickel-based chemistry. The PTM-328 utilizes Nickel-Metal Hydride (Ni-MH), which is safer and more environmentally friendly than the older Nickel-Cadmium (Ni-Cd) technology. Crucially, Ni-MH suffers significantly less from the "memory effect"—a phenomenon where batteries lose maximum capacity if recharged before being fully depleted. This allows users to top up their PRO5150 radio at any time without degrading the long-term lifespan of the cell, maximizing your return on investment for large fleet deployments.



Use Scenarios

Wildland Firefighting Support
Fire crews operating in remote areas rely on the HT1250 for coordination. Charging opportunities are scarce. The 2000mAh capacity of the PTM-328 provides the necessary endurance for long operational periods on the fire line. The rugged housing resists the heat and physical impact common in these environments, ensuring the lifeline back to incident command remains unbroken.

Petrochemical Plant Operations
In large refineries, maintenance teams use intrinsically safe-rated radios (check specific certifications) or standard GP338 units. The environment is noisy, requiring high volume settings, and the distances require high transmission power, both of which drain batteries quickly. This high-capacity battery supports the heavy current draw required for frequent communication across the plant, preventing radio failure during critical maintenance procedures.

Hospital Security Networks
Hospital security staff work rotating shifts covering 24/7 operations using MTX850 radios. Radios are often handed off from one guard to the next and placed in chargers multiple times a day. The PTM-328’s resistance to memory effect is vital here, as it tolerates irregular charging cycles better than older Ni-Cd packs, ensuring the night shift guard doesn't inherit a radio with a "ghost charge" that dies an hour into their patrol.

FAQ

Does this battery come with a belt clip?
Yes, the PTM-328 is typically supplied with a compatible spring-action belt clip included in the box, allowing for immediate deployment.

Will this battery charge in my original Motorola charger?
Yes. Since it is designed as a direct replacement for the HNN9008/HNN9013, it fits and charges correctly in standard Motorola desktop chargers and gang chargers designed for the GP/HT/PRO series.

What is the expected cycle life of this Ni-MH battery?
Under normal usage and proper maintenance conditions, the PTM-328 is rated for approximately 400-500 charge/discharge cycles before capacity begins to noticeably degrade.

Do I need to fully discharge the battery before charging it?
While Ni-MH has less memory effect than Ni-Cd, it is still good practice to perform a full discharge and recharge cycle once every 1-2 months to calibrate the cells and maintain optimal capacity.

Is this battery compatible with the Motorola MTX9250?
Yes, the PTM-328 is fully compatible with the MTX9250, as well as the MTX850 and MTX950 models.