The Battery Tender 021-0134-DL-WH is a 10-bank shop charger in which each of its ten channels delivers its own 4 A output, so a workshop or collection of 6V and 12V batteries can be charged and held at full from one plug. Each bank has its own chemistry selector and voltage selector, and each bank runs its own complete ISM cycle at full 4 Amp output, independent of every other bank. That per-bank independence is the real advantage over a row of single-output chargers: one bank finishing its cycle does not change how another bank behaves. The configuration on Bank 1 has no effect on Bank 6. The charger also automatically monitors and maintains the battery at full charge, which makes it practical for stored vintage cars, motorcycles, and fleet batteries that sit for weeks between uses. Search terms this unit fits include 10 bank battery charger 6V 12V, multi-battery shop charger, and AGM and LiFePO4 maintainer.
Compared with a cheaper trickle charger, the case for this unit is safety and range. It will not produce an output voltage until it senses at least 2 volts from a Standard/AGM lead-acid battery or 4 volts from a Lithium Iron Phosphate battery, and the manufacturer notes it will not start on a battery below those thresholds, so it will not try to force a deeply dead pack. The manufacturer rates the bank for batteries from 14Ah to 100Ah at 6V or 12V. This is a wall-powered bench unit rather than a vehicle-mounted part, so there is no wiring into the car. The manufacturer's manual advises against placing the charger directly above the battery being charged, since battery gases can corrode it, and against setting batteries on top of the unit.
Yes. The manufacturer states that each bank supports both 6V and 12V operation through its own voltage selector, so a vintage 6V battery and a modern 12V battery can charge side by side.
Details vary on this point. The manufacturer describes lithium selection on a per-bank basis, but details on 6V lithium support differ, so confirm with the manufacturer before connecting a 6V lithium pack.
No. According to the manufacturer's manual, the charger will not start on a battery below 2 volts for lead-acid types or below 4 volts for LiFePO4 batteries.
Yes. The manufacturer states that each bank independently enters float maintenance once its battery is fully charged. For batteries without removable cell caps, the manufacturer advises following the battery maker's own recharging instructions.
There is no vehicle wiring involved. Setup is a plug-in process: set the voltage and chemistry selector for each bank to match its battery, clip each lead to the correct battery terminals, and then connect the AC cord. The manufacturer's manual notes that a flashing 6V or 12V LED indicates the charge cycle is prevented from starting or continuing, so check the status lights on each bank before walking away. Keep the unit off the battery's gas path and never stack a battery on the charger, as noted above. Owners on user forums have not been cited here, so treat the install as a low-difficulty task that needs only a wall outlet and a clean working area.
