This four-part mini-series will review the main types of battery chargers: AC-to-DC, DC-to-DC, and Solar. This article isn't a product review or a scholarly journal... it's an overview intended to help you identify the best charging system for your application.
For this review's purpose, we will look at 12v systems used in an off-grid application.
AC-to-DC chargers are probably the most familiar charging system of the lot. Most of us use them every day to charge laptops, cell phones, tablets, or other personal electronic devices.
AC-to-DC Chargers fall into two main groups. First, you have the plug-in portable battery chargers. The second group is comprised of larger units that are typically permanently mounted, such as the Victron MuliPlus. Those are very cool, but an animal all their own. This article will focus on the smaller, more portable chargers.
The PROs for AC-to-DC Chargers are as follows:
- AC power is plentiful. We all have outlets in our homes.
- They're cost-effective. Cheaper per watt than solar or DC-to-DC
- They don't directly depend on the Sun (solar) or another fuel (generator).
The fact of the matter is, AC-to-DC chargers are simple and easy to use. As long as the charger itself is functional and the AC outlet works, you'll be able to charge your battery. It's a concept so simple that it's hardly worth an explanation...which is a significant benefit of this type of charging system.
Because they're so simple, and because they don't require the addition of other componentry, AC-to-DC chargers are a very effective way of charging your batteries.
The difference in price point comes down to speed. The more you spend, the faster you can charge your batteries. You can check out our Ramble Why Lithium for information about why lithium excels at recharging.
The simple way to gauge how quickly your battery will recharge is to take the number of Amps the charger outputs, divided by the battery's Amp Hour capacity, and add 15%.
Example: 25amp(charger)/100AH(Battery) = 4 hours * 1.15 = 4.6 hours to charge.
The only CON that AC-to-DC chargers have is that they need AC power. So when you're boondocking on the north rim of the Grand Canyon, you might have trouble finding an outlet. More to come on that topic later in this series...
If you plan to charge exclusively from an AC-to-DC charger and want to be off-grid, you'll want to make sure you size your battery storage capacity appropriately. To get started, check out our Personal Power Predictor. It's a simple online calculator that will let you know how many days you can camp between needing to find AC power.
What do we use?
We have found a 10-amp Victron IP65 charger has proven to be more than sufficient for everyday NPS charging. This charger allows the NPS to charge overnight from empty.
We also run a 17-amp Victron IP67 charger in Mark’s travel trailer. This charger allows them to recharge faster when off-grid. Either by using a generator or plugging in during a lunch stop at a restaurant. Ideally, we would have gotten the 25 amp version, but the 25 amp unit was out of stock at the time, and we are impatient.
At the end of the day, in the proper application, an AC-to-DC charger is a cost-effective solution that keeps your battery system functional. If you operate within the means of your battery capacity or generally travel to areas with shore power, it could be the only charging system you'll need.
We genuinely appreciate your support.
MARK & AJ
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