High Efficiency 5A Battery Charger by Battery Tender

Five amps of intelligent charging at either 6V or 12V, for both lead-acid and Lithium batteries — the Power Tender® 5 Amp 12V/6V is the highest-output dual-voltage Multi-Chemistry charger in the Battery Tender® standard lineup, delivering ISM (Infinite Sequential Monitoring™) precision to large automotive, marine, and commercial vehicle batteries that need real charging speed alongside long-term maintenance capability.

5 Amp Output — Built for Large Battery Recovery

At 5 Amp, the Power Tender® charges large automotive and marine batteries four times faster than a standard 1.25 Amp charger during the bulk phase. For deep-cycle batteries, large AGM automotive batteries, and marine house batteries in the 60Ah to 150Ah range, 5 Amp bulk charging is the threshold where recovery time becomes practical for working vehicles. Full 5 Amp output is delivered at either voltage setting with no reduction when switched.

Multi-Chemistry: Lead-Acid and Lithium

A manual chemistry selector switches between lead-acid and Lithium (LiFePO4) charging profiles. Lithium batteries require distinct absorption voltages and a different maintenance protocol than lead-acid — the Power Tender® 5 Amp delivers the correct ISM profile for each chemistry at full 5 Amp output and either voltage. For garages transitioning from lead-acid to Lithium, or running both simultaneously, a single unit handles all configurations correctly.

ISM: 4-Stage Charging at 5 Amp

• Initialization — Battery health check and polarity confirmation before current flows at the selected voltage and chemistry
• Bulk Charge — Full 5 Amp output restores depleted capacity at the correct voltage for the selected chemistry
• Absorption — Current tapers automatically as the battery approaches full charge, preventing overcharge damage for lead-acid and Lithium alike
• Float Maintenance — Correct maintenance protocol for the selected chemistry delivered 24/7, indefinitely, without overcharging

Compatible battery size range: 20Ah to 150Ah at 6V or 12V. Lead-acid: flooded, AGM, gel cell, and sealed maintenance-free. Lithium: LiFePO4.

6V Applications

• Antique and vintage automobiles with large 6V batteries
• Antique farm and commercial equipment
• Vintage trucks and machinery with 6V systems
• Any large 6V lead-acid or Lithium battery from 20Ah to 150Ah

12V Applications

• Full-size trucks, SUVs, and commercial vehicles
• Boats with large 12V house or starting batteries
• RVs and campers with deep-cycle battery banks
• ATVs, UTVs, and powersports with larger battery configurations
• Agricultural equipment
• Any 12V lead-acid or Lithium battery from 20Ah to 150Ah

Automatic Temperature Compensation

Charge voltage adjusts automatically based on ambient temperature at both 6V and 12V settings — increasing in cold conditions to ensure complete charging, 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
• ETL and CETL certified

Float Maintenance After Every Charge

After completing bulk and absorption charging, ISM transitions to the correct float maintenance protocol for the selected chemistry automatically — indefinitely. Batteries can remain connected for the full storage season without supervision. Sulfation in lead-acid batteries is prevented entirely. Battery life consistently extends from 2–3 years to 5 years or more regardless of battery size.

3-Year Limited Warranty | DeLand, Florida Since 1965

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