Choosing Battery Tenders & Chargers

The World's Most Advanced Battery Charger!  Longer Battery Life, Less Maintenance

Our individual pages list the recommended uses for each type of Tender and Charger but as a consumer, you will need to consider a few things to determine the best option for your battery and application requirements:

• What type of battery will be recharged?  Lead Acid, Sealed, VRLA, AGM, GEL, etc...
• How large is the battery?  This is the capacity in amp hours.  Some batteries will not have this number displayed on their label.  Typical labels will show either CCA ( Cold Cranking Amps ) or Reserve Capacity in Minutes.  Reserve capacity is the number of minutes that the battery can deliver a constant 25 amps to a load.
• How is the battery being used?  What is the application?  SLI, Deep Cycle, or Standby Power?
• How deeply will the battery be discharged?  Shallow cycling (discharging 20% to 50% of the battery’s capacity) does not usually require as much recharge power as deep cycling (discharging more than 50% of the battery’s capacity).
• How often will the battery be discharged?  In general, the more often the battery is discharged, the higher the power you want to use to recharge the battery.  This is particularly important if the battery is deeply discharged.  A good rule of thumb for deep cycle batteries is to only discharge them once every 24 hours, otherwise there may not be sufficient time for the batteries to recover between discharges.  This has been a serious point of concern for many industrial applications.  It has also been a great disappointment to many consumers who have expected to be able to repeatedly discharge large deep cycle batteries and then recharge them with low power chargers.
• How much time is available to recharge the battery before it has to be discharged again?  This question is where many industrial systems designers get into trouble.  Industrial battery use is usually the most demanding, particularly with electric vehicles that require a mixture of high and moderate rate deep discharges.  Time must be allotted not only to recharge the battery, but also to let it rest in a fully charged state between deep, high rate discharges.  If you need to replace 100 amp hours in 4 hours, then you need at least 25 amps.  However, the truth is that you will need 30 to 40 amps or more and probably 6 to 8 hours because of the way that chargers and batteries behave after the battery is 80% recharged.  It is more difficult, and it takes a lot longer to replenish the last 20% of the battery charge than it does to replenish the first 80% of the battery charge.  Even if you can get the battery completely recharged in 6 to 8 hours from a deep discharge, it is still not wise to deeply discharge a lead acid battery more than once a day.

The Battery Tender solves the task of properly charging all lead acid technologies by automatically applying the correct charging logic algorithm (a mathematical formula for solving a problem.)  Cycle life is critical to not only the battery manufacturer but also to the end user.  Temperature compensation, consistent amperage output, voltage control, and correct float levels ensure that the battery will be revived and maintained at an optimum level throughout its designed life span.  The Battery Tender has the advantage of both charging and float modes and the float mode establishes an output voltage which is well below the gassing voltage of a lead acid battery.  This keeps the battery "topped off" while minimizing any detrimental effects.  Electronic circuitry, controlled by an onboard microprocessor, performs the complex switching functions.  Ordinary trickle chargers do not have the advantage of sophisticated electronic control. 

Battery Tender chargers offer a variety of power levels:  7.5, 15, 70, 300 & 600 watts, maximum charge currents:  0.75, 1.25, 2, 3, 4, 6, 10, 15 & 20 amps.  Nominal battery voltages: 6, 12, 24, 36 & 48 volts.  Various charging algorithms are available to accommodate the wide range of lead acid battery styles:  Lead Acid, Seales, VRLA, GEL, & AGM.

After you've considered your battery type, the size, and how it will be used - you can make a more informed choice regarding the charger you will need.  The table below lists the full line of Deltran's automatic, linear regulated, switch-mode power converter, and microprocessor controlled chargers in a variety of power levels: 7.5, 15, 70, 300 & 600 watts, maximum charge currents: 0.75, 1.25, 2, 3, 4, 6, 10, 15 & 20 amps, and nominal battery voltages: 6, 12, 24, 36 & 48 volts.

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