Battery Tender Battery Chargers

Battery Tender Battery Chargers: The Original Smart Charger

When it comes to keeping batteries healthy during storage or light use, few names carry the authority of Battery Tender. Made by Deltran, a family-owned company based in Central Florida, Battery Tender has been engineering battery maintenance solutions since 1965. In 1988, Deltran pioneered what would become an industry standard: the world's first fully automatic smart battery charger — a development that fundamentally changed how enthusiasts, collectors, and professionals think about battery care.

What separates Battery Tender from a conventional trickle charger is the intelligence built into every unit. Battery chargers in the Battery Tender lineup use microprocessor-controlled charging programs to regulate the precise charge algorithm a battery needs, rather than blindly pushing current into a battery whether it requires it or not. This eliminates the risk of overcharging and sulfation — two of the most common causes of premature battery failure.

ISM Technology and 4-Stage Charging

At the heart of Battery Tender's most capable chargers is ISM (Infinite Sequential Monitoring™), a proprietary technology that continuously evaluates battery condition throughout the charging process. ISM delivers a precise 4-stage charge sequence — Initialization, Bulk Charge, Absorption, and Float — ensuring the battery receives exactly the energy it needs at each phase, then transitions to a safe maintenance mode once fully charged. This "set it and forget it" design means you can leave a Battery Tender connected indefinitely without worrying about damage.

Coverage Across Voltages and Battery Chemistries

Battery Tender's charger lineup spans a wide range of applications. Their smart chargers are built to handle 6V, 12V, 24V, 36V, and 48V batteries automatically, making them suitable for everything from motorcycles and ATVs to cars, RVs, marine vessels, and even industrial fleet equipment. The lineup supports multiple battery chemistries including flooded lead-acid, sealed maintenance-free, AGM, Gel Cell, and lithium (LiFePO4) batteries — with specific models designated for each chemistry to ensure safe, proper charging.

Flagship Product Lines

• Battery Tender Plus: The iconic 1.25A smart charger trusted by motorcycle owners, classic car collectors, and powersports enthusiasts for decades. Includes a quick-connect harness for easy hookup, reverse polarity protection, and a 10-year warranty.
• Battery Tender Junior: A compact, lower-output option ideal for smaller batteries and vehicles with minimal parasitic drain during storage.
• Weatherproof Industrial Chargers: Heavy-duty units such as the 12V/24V 5A model designed for fleet and commercial applications where durability in harsh conditions is essential.
• Charge N Start Series: A 2-in-1 smart charger and jump starter combining long-term battery maintenance with emergency starting capability in a single device.

Who Trusts Battery Tender?

Battery Tender has earned its reputation as the preferred choice of collectors, dealers, fleet owners, racers, and OEM partners alike. The brand's quick-disconnect harness system makes it practical to leave leads permanently on a battery, so plugging in becomes as effortless as parking the vehicle. Whether you're storing a vintage car over winter, maintaining a fleet of powersports vehicles, or keeping a marine battery topped off between outings, Battery Tender's smart chargers are engineered to protect your investment for the long haul.