Battery Tender® 3 AMP Power Tender® 12V / 6V Switchable Battery Charger

When a battery needs more than maintenance charging — when it is deeply discharged, slow to respond, or simply too large for a 1.25 Amp charger to recover efficiently — the Power Tender® 3 Amp 12V/6V is the step up. Triple the output of the Battery Tender® Plus at either 6V or 12V, with Multi-Chemistry support for both lead-acid and Lithium batteries, and the same ISM (Infinite Sequential Monitoring™) intelligence that has protected batteries since 1965.

Built for Faster Recovery on Larger Batteries

The Power Tender® 3 Amp delivers full 3 Amp output at either 6V or 12V — three times the output of the standard Plus at the same voltage. For automotive batteries from 14Ah to 100Ah that have sat discharged for extended periods, 3 Amp bulk charging recovers capacity significantly faster without the risk of overcharge that comes with unregulated high-output chargers.

Multi-Chemistry: Lead-Acid and Lithium

A manual chemistry selector switches between lead-acid and Lithium (LiFePO4) charging profiles, delivering the correct absorption voltage and float protocol for each battery type. Select lead-acid for flooded, AGM, GEL, and sealed batteries; select Lithium for LiFePO4 batteries in modern vehicles and upgraded powersports applications. ISM adapts its full 4-stage algorithm to the selected chemistry automatically.

ISM: 4-Stage Charging at Full 3 Amp Output

• Initialization — Battery health check and polarity confirmation before current flows; adapts to the selected voltage and chemistry
• Bulk Charge — Full 3 Amp output at 6V or 12V restores depleted capacity efficiently
• Absorption — Current tapers automatically as the battery approaches full charge, preventing overcharge damage at the correct voltage for the selected chemistry
• Float Maintenance — Precisely regulated micro-current delivers the correct maintenance protocol for lead-acid or Lithium indefinitely, 24/7, without overcharging

Compatible battery size range: 14Ah to 100Ah at 6V or 12V. Lead-acid: flooded, AGM, gel cell, and sealed maintenance-free. Lithium: LiFePO4.

6V Applications

• Classic and antique automobiles with 6V systems
• Vintage motorcycles and pre-1960s vehicles
• Antique tractors and farm equipment
• Any 6V lead-acid or Lithium battery from 14Ah to 100Ah

12V Applications

• Cars, trucks, and SUVs
• Motorcycles and touring bikes
• ATVs and UTVs
• Boats and marine vessels
• Recreational vehicles
• Lawnmowers and garden tractors
• Any 12V lead-acid or Lithium battery from 14Ah to 100Ah

When to Choose the Power Tender® Over the Plus

The Battery Tender® Plus 1.25 Amp is the correct choice for ongoing maintenance of batteries that are regularly charged. The Power Tender® 3 Amp is the correct choice when batteries need actual recovery — vehicles that sat all winter without any maintenance charger, larger automotive batteries that take days to recover at 1.25 Amp, or any application where charging speed and Lithium compatibility matter alongside long-term maintenance capability.

Automatic Temperature Compensation

Charge voltage adjusts automatically based on ambient temperature at both voltage settings — increasing in cold conditions to ensure a complete charge, reducing in heat to prevent overcharging and gassing. Correct voltage delivered year-round without manual adjustment.

Safety Features

• Spark-proof connection — No current flows until polarity and connection are confirmed correct
• Reverse polarity protection — Automatic shutdown if connections are reversed, protecting Lithium BMS systems and vehicle electronics
• Short-circuit protection — Automatic fault detection and shutdown
• ETL and CETL certified

Sulfation Prevention at 3 Amp

Sulfation — the permanent, irreversible hardening of lead sulfate on battery plates — occurs when lead-acid batteries sit discharged. The Power Tender® 3 Amp transitions to ISM float maintenance automatically after charging is complete, holding the battery at peak voltage indefinitely. Battery life consistently extends from 2–3 years to 5 years or more.

3-Year Limited Warranty | DeLand, Florida Since 1965