Note: This page contains links (Highligted in Red) directly to Amazon's Product pages where you can read other people's opinions of the listed Battery Charger which I would encourage you to do. I like to sort them by date so that I can see the most current and relevant Battery Charger reviews first as products do change over time. I personally own the C-TEK Multi US 7002 which I purchased from Amazon (Was not avaliable locally) and I Love the thing! On my van I can trickle charge straight through the Cigarette Lighter port. Newer vans have complex electronics which may make this optiona unavialable. I also own a Battery Minder (VDC Electronics) trickle charger that has served me will for more than a decade. I bought the Battery Minder online from a dealer I can not remember. In this day and age of Big Box Retailers it can be difficult to find higher end (Non Chinese) products... so the only option may be to purchase online. I like to support local businesses when I can.
There is an entire world of knowledge to be learned when it comes to batteries and chargers, this article will make no attempt to dig in too deep technological level, but instead will cut to the chase about what most people want to know. I’m basing this information on my experience with chargers and research I’ve been doing for maintaining deep cycle house batteries for dry camping use.I’ll address Solar Chargers in another article when I have more time.
Again this is less an attempt to “Dumb Down”, than to “Save Time”. People are busy and learning everything there is to know about batteries is frankly quite boring. So my attempt here is to cut to the chase and tell you what you need to know to find the right charger for your application
If you simply want to know what brands (And why wouldn't you?) I recommend here they are with links to Amazon so you can read further reviews I am also including the URL of the Manufactures so you can learn more about each model.
- VDC Electronics - "BatteryMinder"” (Not to be confused with “Battery Tender”) I own the Model# 12117, if it’s in your budget get the Model# 2012 both can charge standard and AGM Batteries. These are low amp charger/maintainers which you leave on as long as you like. If you want to charge faster they offer a Model# 12248 which is an excellent choice if you charge a lot of starter batteries as well. For quick charging above 10 Amps see CTEK and Xantrex below. Keep in mind with most Deep Cycle Batteries you don’t want to push more than 10% of the Amp hour capacity for very long. So if you are running a single deep cycle battery with 100ah capacity and a low wattage inverter (i.e. 300-700 watt) 10 amps is just fine. But if you are charging banks of batteries you’ll need more “umph” (Not a technical term). A 400ah bank of deep cycle batteries would be fine to charge with a 40amp charger until it reaches a maintenance level to top off. Mfg Site: www.BatteryMinders.com
- CTEK – The Models Multi US 3300 and Multi US 7002 are excellent chargers and on par with the VDC line up. Mfg Site: www.Ctek.nu
- Xantrex - for RV Deep Cycle Batteries that need high Amperage or charging from Generator. I’d recommend the Model True Charge 2 (Available in 20, 40, 60 amp). These are not cheap! You may also consider their Inverters with Built in Chargers. Mfg Site: www.Xantrex.com
Buying a quality battery charger will SAVE YOU MONEY. Buying a cheap charger may charge your battery when it goes dead, but it will not save you any money. I’ve been using a BatteryMinder from VDC on my Custom Camper Van for 9 years now with the same Costco Battery. Keeping the battery “Topped Off” and “Desulphated” can double or triple the life of your battery! Sulfation is the cause of early battery failure. Sulfation can be safely dissolved by keeping the battery charged with a charger that utilizes a pulse frequency program and low voltage. A quality maintenance charger will offer this feature. I would not purchase a battery charger that did not incorporate this technology. My van battery at Costco was about $75 in 2003 and the charger cost me only $45… and I use it on other vehicles as well… so you can easily “do the math” and see the advantages to maintaining batteries. It costs about 15 cents a month in electricity to run in maintenance mode and you can charge up to 5 batteries at once with the version I purchased.
What is Sulfation (sul-fay-shun) and How Does It Affect Batteries?
When batteries are improperly maintained (over-under charged or left uncharged for extended periods) small crystals of sulfuric acid from the battery's electrolyte (liquid or paste) form on the battery's charge plates. They act as a resistor (barrier) preventing the battery from ever again accepting a full charge, no matter how long a charging source may be connected. Once this occurs, the cranking power of the battery is severely reduced, as well as its life. – Source VDC Electronics the maker of “BatteryMinder” Chargers.
Battery Choices by Application Use
The first thing one should know is there are essentially 3 types of designs used in 12 volt batteries for RV use and three basic chemistries.
- Starter Batteries – designed for high cranking amps for a brief period of time and generally plain lead acid.
- Combination Starter/Deep Cycle Batteries – designed with both high cranking amps and a longer cycle life
- Deep Cycle – designed to be drawn down and recharged.
Starter batteries will have a very short life if you try and use them to run DC appliances… the plates and chemistry are not designed for it. So if you plan on using a cigarette lighter adapter type Inverter you should not plan on using it much unless your car is running other wise it will put undue strain on your starter battery.
Combination batteries are best used as starter batteries where larger loads like Stereo Systems, DVD Entertainment, GPS, etc., along with parasitic draw accessories are present. In short if you have a lot of gadgets in your vehicle this would be a good choice for a starter battery.
True Deep Cycle Batteries are what you want if you plan on running an Inverter or RV for lighting, laptop computers, televisions, etc. I’m no going to get into how many batteries or the amp hours needed to drive your RV in this short article which is intended to talk about Battery Charging. I hope to get into that in another article.
Battery Chemistry and Charging
There are different plate materials and chemistries which will require a different approach to charging. The two battery types you should be concerned with are:
- Standard Lead Acid Batteries
- AGM (Absorbed Glass Matt)
The advantage of the latter (e.g. AGM) is they are manufactured in a way that the electrolyte is suspended and vented internally so you can use them inside a vehicle with little risk… as they will not spill. You can install AGM batteries on their side if you wish. Let me address “Gel” batteries briefly. Gel is just something added to the electrolyte so it won’t spill however Gel batteries should be avoided as they require very specific charging algorithms and can be easily damaged if not properly charged. In addition there are ZERO BENEFITS to Gel vs AGM. Now that AGM is readily available I see almost no application in an RV where one would purchase Gel vs AGM. Perhaps there are applications in home solar systems, but not for RV mobile use. Most people selling batteries at Walmart or Costco or even many auto parts stores do NOT know the difference. AGM batteries are NOT Gel batteries. There are many differences which I am not going to get into here. If you want a brief overview that explains it better than I can you can read this article at Battery Stuff: www.BatteryStuff.com/kb/articles/battery-articles/gel-vs-agm.html
Note: These recommendations are not exclusive as there are other brands that will work fine, but in my research and experience this is what I own or recommend. I generally purchase from Amazon because of the free shipping and no tax, but you should purchase wherever you get the best service and price obviously. Amazon does compensate me for items purchased from their site but only if purchased within 24 hours. This has no effect on the pricing as they do not discount or raise prices based on links to their site. Sadly as much as I’d like to recommend American Made these companies while they may or may not be based in the USA still outsource their manufacturing to the Far East.