For most of us, simply knowing to add a high-quality AGM battery like the XS Power D Series covers the bases. It gives more power than most of us need, it can last a long time while the truck is off, and it’s available in a direct-fit size for most diesels. If you’re purchasing replacement batteries only because one or both of your batteries went bad, the assurance of a top tier brand like XS Power is enough. But some of us are replacing factory-equipped batteries that are still good because our trucks’ electrical demands are greater than the stock batteries can handle. We need batteries that put out more juice to the starter, ones that last longer, and ones that can handle extreme lower temperatures while cranking over a heavy diesel engine. For those of us that demand more from our batteries, there are two specified measurements that we are really concerned with: Reserve Capacity (RC) and Cold Cranking Amperage (CCA). A higher CCA will dictate a stronger starting in icy climates. While this may not be relevant for owners in warmer climates, Cranking Amperage (CA) is always higher than the CCA, so you’re covered. Reserve Capacity can get mixed up with Amp Hours, but RC is a measurement of time based on a 25-amp draw while Ah is the amount of current that can be pulled from the battery in one hour. Since they are related you can use one to figure out the other, but RC is the one you’re going to be concerned with if you’re wondering how long you can run a winch, inverter, or stereo with the truck turned off.
We recommend sticking with the same battery on both sides in a dual battery setup. You can certainly mix and match as long as you’re using a 12-volt based battery, but sticking with the same groups size and type of battery on each side will be your best bet. For heavy duty diesel applications, we still prefer an AGM battery over a lithium or standard lead acid battery, due to their longevity and ability to keep giving power even when voltage drops.
XS Power D4800 Dual Batteries
While XS Power has direct-fit Lithium batteries for Rams, Super Dutys, and Duramax trucks that could drop almost 100 pounds out of the engine bay, we still recommend going with AGM batteries in diesel applications—especially ones that have external power needs like winches, plows, or inverters that put large drains on batteries with the truck off.
Battery Specs / Terms
Volts (V)—Amount of energy given to an electronic circuit. The voltage of a battery at full capacity is called Charge Voltage.
Cranking Amps (CA)—Measure of current available for 30 seconds at a temperature of 32 degrees F while maintaining a voltage of at least 1.2 volts per cell (6-cell setup in automotive batteries)
Marine Cranking Amps (MCA)— Measure of current available in marine applications for 30 seconds at 32 degrees F while maintaining a voltage of at least 1.2 volts per cell (usually the same as CA)
Hot Cranking Amps (HCA)—Measure of current available for 30 seconds at 80 degrees F while maintaining a voltage of at least 1.2 volts per cell
Cold Cranking Amps (CCA)—Measure of current available for 30 seconds or more in temperatures of 0 degrees F or colder while maintaining a voltage of at least 1.2 volts per cell
Reserve Capacity (RC)—Number of minutes that a fully charged battery can discharge 25 amps while maintaining a voltage of at least 1.75 volts per cell, while receiving no external supplement charge (like an alternator or charger). Note that reserve capacity is lessened in extreme cold and hot climates.
Amp Hours (Ah)—Amount of current that can be produced in one hour. By knowing the Amp Hours, you can find the Reserve Capacity by multiplying by 2.4. RC = Ah x 2.4
Deep Cycle—Battery type that stay within an effective operating voltage until 80% of its energy is depleted. A deep cycle battery can endure more discharge/charge cycles than a typical starting battery. While there are some hybrid deep cycle starting batteries, they are usually two different types of batteries.
Absorbent Glass Mat (AGM)—Type of Valve-Regulated Lead-Acid (VRLA) battery that is sealed, non-spillable, and can be mounted in any position. The AGM battery uses fiberglass matting to hold electrolytes in place on thin lead plates instead of the free-flow liquid design of a standard battery. It has a lower internal resistance and can be discharged more times in its life than a standard lead-acid battery.
Which Battery To Hook Accessories To
Theoretically, it should not matter what battery you hook any supplemental accessories to as they are both joined together in parallel (except for the starter), but logically it would make sense to use the battery furthest from the fuse box. We would suggest relying on practicality: Don’t run power cables over the engine or radiator, and keep the wires as short as possible. For wires running through the firewall on the driver’s side, of course we’ll use the driver’s side battery. But for large power cables that don’t need to enter the cab like winch wiring, we’ll run to the passenger-side battery.
XS POWER D4800 SPECS:
- Primary Watts-2,000
- Secondary Watts-3,000
- Weight-48.2 lbs.
- Dimensions-L 10.9″ x H 7.5″ x W 6.9″