Product Description

BatteryTender Plus is the most advanced charger/maintainer on the market specially designed for today's sealed lead acid batteries. The BT Plus uses micro-processor technology in a four stage charging profile to charge, improve, and float your battery so it is ready when your are. Constant current charging and regulated voltage patterns allow the battery to be recharged fully and safely without the fear of overcharging.

Product Details

• Amazon Sales Rank: #7 in Automotive
• Color: Black
• Brand: Battery Tender
• Model: 021-0128
• Released on: 2006-12-01
• Dimensions: 11.00" h x 4.00" w x 11.00" l, 2.30 pounds

Features

• Solid state two color LED indicates stage of charger; a quick connect harness for use in hard to reach areas
• Perfect for all lead-acid, flooded or sealed maintenance free batteries (AGM and gel cell)
• Complete 4-step charging program (initialization, bulk charge, absorption mode and float mode) that maintains batteries at full charge without overcharging via its 4-step charging system
• Automatically switches to float/maintenance mode voltage after fully charging the battery
• Temperature compensated to ensure optimum charge voltage according to ambient temperature, and spark proof and reverse polarity protected; 10-year limited warranty

Amazon.com Product Description

The Battery Tender Plus 12-volt/1.25-amp Battery Charger is the convenient solution to the challenge of keeping 12-volt vehicle batteries optimally powered when not in use. It is able to charge any lead-acid battery--including standard and sealed AGM and Gel Cell battery types and is also designed to be easy to use in difficult spaces, to utilize a 4-step charging program and safely function in a fully automatic mode. Taken together this makes the Battery Tender Plus 12-volt/1.25-amp Battery Charger an excellent means of ensuring that your battery is fully charged and ready to go when you are. 4-step charging with automatic float mode. View larger. The 4-step charge cycle detailed. View larger. Safe, 4-step Battery Charging The Battery Tender Plus 12-volt/1.25-amp Battery Charger is much more than a trickle charger. Powered by BTP microprocessor technology, it has a "brain". Utilizing a 4-step charging program (initialization, bulk charge, absorption mode and float mode), it allows you to simply connect the charger to a battery, either in or out of a vehicle, and forget about it until you are ready to put the battery to work. Like all Battery Tender chargers, at the end of the regular charger cycle the it automatically switches its output voltage to a safe, storage or float level that eliminates the need to worry about the damaging effects of overcharging, and the resulting need to check on the condition of the battery. If or when the battery voltage drops too far under load, output power resumes and the charging cycle begins again. The unit also features sparkproof connectors, short circuit and reverse polarity protection, an easy to understand charging status LED indicator, a quick connect harness for use in hard to reach areas and almost no current draw from batteries connected to. Key Features: Perfect for all lead-acid, flooded or sealed maintenance free batteries (AGM and gel cell). Complete 4-step charging program (initialization, bulk charge, absorption mode and float mode). Automatically switches to float / maintenance voltage after fully charging the battery. If the battery voltage drops too far under load, full charger output power resumes. Temperature compensated to ensure optimum charge voltage according to ambient temperature. Solid state two color LED indicates stage of charger. Spark proof and reverse polarity protected. Includes quick connect harness for use in hard to reach areas. 10 year warranty. Charger Models Output Voltage Output Current Charging Software*/ Battery Type AC Voltage/ Frequency Input (Volts) (Amps) Battery Tender Junior 6V Battery Charger 6V 0.750A 3 Step STD & AGM 120 VAC, 60 Hz Battery Tender Junior 12V Battery Charger 12V 0.750A 4 Step STD & AGM 120 VAC, 60 Hz Waterproof 800 12V Battery Charger 12V 0.800A 3 Step STD & AGM 100 to 240 VAC, 50/60 Hz Battery Tender Plus 6V Battery Charger 6V 1.25A 4 Step STD & AGM 120 VAC, 60 Hz Battery Tender Plus 12V Battery Charger 12V 1.25A 4 Step STD & AGM 120 VAC, 60 Hz Battery Tender Plus 12V Battery Charger (Gel Cell) 12V 1.25A 4 Step STD & AGM or GEL 120 VAC, 60 Hz Battery Tender Twin 800 12V Dual Battery Charger 12V 0.800A 3 Step STD & AGM 100 to 240 VAC, 50/60 Hz Battery Tender 12V 2-Bank Battery Management System 12V 1.25A 3 Step STD & AGM 100 to 240 VAC, 50/60 Hz Battery Tender 12V 4-Bank Battery Management System 12V 1.25A 4 Step STD & AGM 100 to 240 VAC, 50/60 Hz Battery Tender 12V 5-Bank Battery Management System 12V 2.0A  4 Step STD & AGM 120 VAC, 60 Hz Battery Tender 12V 10-Bank Battery Management System 12V 2.0A  4 Step STD & AGM 120 VAC, 60 Hz *Note: All Deltran battery chargers will charge all types of lead acid batteries: either flooded (standard STD), sealed maintenance free Absorbed Glass Mat (AGM), or sealed maintenance free gelled electrolyte (GEL) batteries. However, for optimum battery performance in deep cycle applications (for example, running a trolling motor), it is best to chose the Deltran charger that has the charging software specifically designed for the battery type. Fortunately, since the technical staff at Deltran has developed charging software that works equally well for both STD & AGM batteries, the only choice to be made is between 2 models: either STD & AGM or GEL software. 10-Year Limited Warranty Deltran provides a limited 10-year warranty on its Battery Tender Plus 12-volt/1.25-amp Battery Charger to the original purchaser based on defective material or workmanship. Warranty is void in cases of product misuse, disassembly or modification. Other details regarding warranty limitations and procedures are contained in the Deltran Battery Tender Charger's general limited warranty information sheet enclosed with this product.

Customer Reviews

A Must for Garage Queens
Every time I want to fire up my old 71 Datsun (that's Nissan for those of you younger than 30) 240 Z there's a good chance that the battery has drained down and that I can't start it! Looking around at car forums I read about this nifty little gadget....It's like a battery trickle charger....sort of. Whereas it's not recommended to keep a trickle charger hooked up all the time, this one has circuitry to limit the current and sense when the battery needs charging. It only charges at 1.25 amps which is easier on the battery.

I've had it on for a month now and it's great. The first couple of days, the red light was on indicating charging. Since then it's been on green and the car starts right up. I live in Houston where the heat and humidity can be just as brutal on batteries as the cold.

I highly recommend this "tender" for those that have cars that stay unused for long periods.

As other reviews have mentioned it comes with a set of adapters that allow you to permanently attach pigtails to the battery posts and then you can quickly connect the tender without having to use the alligator clips (also included).

For the price and free shipping you can't go wrong!

UPDATE after two years of use.
I can now reconfirm that these battery tenders work great - I've had them hooked up continuously on two cars that stay in the garage a lot and I've NEVER had them not start right up. A quick glance at the LED display lets me know that the batteries are either charging or fully charged. It's a real pleasure to be able to go right up and enjoy your wheels without having to worry about whether the battery is dead. I can't say for sure, but I suspect that it lengthens the life of the battery as well.

A Doozie
This little gizmo is dynamite.

I have a 4 year old Accord that, due to circumstance, only has about 4400 miles. Rarely driven...and what driving is done is mostly at night.

Sat for a week once in very cold weather...dead battery.

Ordered this. Hooked it up. 100% charge and the battery is very powerful once again.( had thought I would probably need a new one).

It's very small size makes it extremely easy to use and store. And it will not overcharge, so you do not have to babysit the process.

It's LEDs glow red when charging. Green and red blink once 80% has been achieved. Solid green at 100%.

It did, in very cold weather, take a long time to establish a full charge on my almost completely discharged battery. The battery would have been usable in a few hours, but 100% took close to 18.

Highly recommended.

A+ Product
I have an older version of this charger that I bought in the mid 90's. I used it to maintain my garaged Mustang's battery over the winter months for many years. I made a cigarette lighter adapter so all I needed to do was to plug it in instead of using the alligator clips. I have to say this thing is dead reliable! It always kept my battery in prime condition. I love it and recommend it highly.