small battery booster box Battery Tender Junior Battery Charger

small battery booster box Battery Tender Junior Battery ChargerFor over 60 years, Battery Tender has been the battery charger that motorcycle dealers recommend, powersports shops rely on, and owners trust to keep their batteries alive through months of storage. The Battery Tender Junior 12V 750mA is America's #1 selling battery maintainer not because it is the cheapest option, but because it works, every time, without supervision. What It Is The Battery Tender Junior 12V 750mA is a fully automatic 12V smart

For over 60 years, Battery Tender® has been the battery charger that motorcycle dealers recommend, powersports shops rely on, and owners trust to keep their batteries alive through months of storage. The Battery Tender® Junior 12V 750mA is America's #1 selling battery maintainer — not because it is the cheapest option, but because it works, every time, without supervision.

What It Is

The Battery Tender® Junior 12V 750mA is a fully automatic 12V smart battery charger and maintainer for lead-acid, AGM, GEL, and sealed maintenance-free batteries from 3Ah to 30Ah. It is the definitive solution to dead batteries after winter storage — and the smart alternative to basic trickle chargers that damage the batteries they are supposed to maintain.

Who It Is For

The Battery Tender® Junior is purpose-built for powersports and small-vehicle batteries that sit unused for extended periods. If your motorcycle, ATV, or personal watercraft spends winter in storage, one Battery Tender® Junior connected from October to April delivers a fully charged battery in spring — every spring, year after year. For batteries larger than 30Ah or vehicles with high parasitic electrical draws, the Battery Tender® Plus is the correct choice.

Why It Beats Every Trickle Charger

A basic trickle charger delivers constant low current regardless of battery state — connected for weeks, it overcharges, causes excessive gassing, consumes electrolyte, and permanently damages internal plate structure. The Battery Tender® Junior uses ISM (Infinite Sequential Monitoring™), Battery Tender®'s proprietary 4-stage charging algorithm that has protected batteries since 1965:

• Initialization — Performs a health check before charging begins; confirms polarity and battery condition before current flows
• Bulk Charge — Full 750mA output efficiently restores depleted capacity
• Absorption — Current automatically reduces as the battery approaches 100% charge, eliminating heat buildup and overcharge damage
• Float Maintenance — Precisely regulated micro-current delivered 24/7 offsets natural self-discharge, holding the battery at peak voltage indefinitely without overcharging

The result: 100% battery capacity when you return in spring, without a single manual adjustment.

Battery Chemistry Compatibility

The Battery Tender® Junior works with all standard 12V lead-acid battery chemistries:

• Flooded (wet cell) — Traditional lead-acid batteries requiring ventilation
• AGM (Absorbent Glass Mat) — Sealed, spill-proof batteries standard in modern powersports vehicles
• GEL — Sealed batteries using gelled electrolyte, found in specialty applications
• Sealed Maintenance-Free — Factory-sealed batteries requiring no electrolyte service

Compatible battery size range: 3Ah to 30Ah at 12V.

Vehicles the Junior Maintains

• Motorcycles and touring bikes
• ATVs and UTVs
• Dirt bikes and off-road vehicles
• Scooters and mopeds
• Personal watercraft
• Snowmobiles
• Lawnmowers and garden tractors
• Classic and collector cars with 12V batteries up to 30Ah
• Boats and marine vessels with small 12V house batteries

Automatic Temperature Compensation

Cold reduces electrolyte conductivity and requires higher voltage to achieve full charge. Heat accelerates overcharge risk and electrolyte evaporation. The Battery Tender® Junior automatically adjusts charge voltage based on ambient temperature throughout the full charging cycle — increasing output in extreme cold to ensure a complete charge, reducing it in summer heat to prevent damage. No manual adjustment required at any temperature, any season.

Safety Features

• Spark-proof connection — No current flows through the clamps until polarity and connection are confirmed correct, eliminating connection sparks that can ignite battery hydrogen gas
• Reverse polarity protection — Unit will not charge if clamps are reversed, protecting battery and vehicle electronics
• Short-circuit protection — Automatic shutdown if an output fault is detected
• ETL and CETL certified — Independently tested and certified for safety in the United States and Canada

Stop Buying Dead Batteries Every Spring

Sulfation is the primary cause of premature battery failure in stored vehicles — the permanent, irreversible hardening of lead sulfate crystals on battery plates that occurs when a battery sits discharged. Unlike surface corrosion, sulfation is a structural change to the battery's lead plates. Once it forms to any significant degree, it cannot be dissolved or reversed by any charger; the battery's effective capacity is permanently reduced. The Battery Tender® Junior prevents sulfation from forming in the first place by maintaining continuous float voltage from the moment it is connected. Battery life consistently extends from 2–3 years to 5 years or more.

A dead battery in spring is not bad luck — it is a preventable failure. One Battery Tender® Junior, connected each fall, eliminates it entirely.

5-Year Limited Warranty | DeLand, Florida Since 1965 | 021-0123