Update 2025:  I do NOT earn a commission from the Amazon Links on this page.  All these links still work and yes my CTEK 7002 is still running strong after 10 years!  I also have Lithium Charges mow which I bought direct from LiTime the Company I purchased my lithium LifePO4 batteries from about 2 years ago.  I can recommend you take a look at them as you can now purchase 100AH LifePO4 batteries for about $200! As of 2025 I am personally using LiTime Lithium LifePo4 batteries.  There are many budget Lithium Batteries on the market I have had very good luck with LiTime so far!  I do NOT have an affiliate relationship with LiTime I make no money from posting about them here.  There are other great options like Battleborn Batteries, but they cost 4x as much and it is the same chemistry!

Let’s Talk Lithium Battery Charging

LiFePO4₄ (Lithium Iron Phosphate) batteries are increasingly popular in RVs, off-grid setups, and portable power stations due to their long lifespan, stable chemistry, and deep discharge capabilities. While many LiFePO4₄ batteries are technically compatible with traditional lead-acid chargers, using one isn’t ideal. Lead-acid chargers typically have a lower charging voltage and different charge profiles, which can result in undercharging or failure to fully balance lithium cells. Over time, this can limit the performance and longevity of the battery. Some LiFePO4₄ batteries include built-in battery management systems (BMS) that allow them to tolerate these inconsistencies, but this doesn’t make it the best long-term solution.

It’s highly recommended to use a dedicated lithium (LiFePO4₄) charger, which is designed to deliver the proper charging voltage and current specific to lithium chemistry—typically with a constant current/constant voltage (CCCV) profile and no float or trickle charging at the end. This ensures faster, more efficient charging and full capacity utilization without stressing the battery. Additionally, lithium chargers help with proper cell balancing, which maintains the health of the battery and extends its service life.

LiFePO₄ batteries are not ideal for use as starter batteries (like in cars or trucks) because they are designed for steady, deep discharges rather than high-current bursts. While they can technically produce a decent amount of current, they lack the cold cranking amps (CCA) and fast energy delivery that’s required to reliably start an internal combustion engine, especially in cold weather. Their strength lies in long-term energy delivery—not short, high-load demands. For starting applications, a dedicated lithium starter battery with different internal chemistry or a traditional lead-acid (AGM or flooded) battery remains the better choice.

There are several lithium battery chemistries available today, each with unique strengths depending on the application. In RV and mobile power systems, LiFePO₄ (Lithium Iron Phosphate) stands out for its thermal stability, safety, and long cycle life. Unlike other lithium chemistries, it’s far less prone to overheating or combustion, making it a safer option for enclosed spaces like campers and vans. Here’s a quick overview of the most common types:

  • LiFePO4₄ (Lithium Iron Phosphate) – Also just called LifePO

    • Very stable and safe

    • Long lifespan (2,000–5,000 cycles)

    • Ideal for deep cycling and mobile/off-grid use

  • Li-ion (Lithium-Ion / NMC – Nickel Manganese Cobalt) *

    • High energy density

    • Common in power tools, laptops, and EVs

    • Less stable than LiFePO4₄, more heat-sensitive

    • Because of the lower weight and higher energy density these can be great for e-bikes.

  • LCO (Lithium Cobalt Oxide)

    • High energy, lightweight

    • Common in smartphones and small electronics

    • Not suitable for deep cycle or high-draw applications

  • LTO (Lithium Titanate)

    • Extremely long lifespan, fast charging

    • Low energy density, very expensive

    • Used in specialized or commercial applications

For RV owners prioritizing safety, reliability, and long-term value, LiFePO4 offers the best combination of characteristics—especially when paired with the correct charger and system setup.

Breakdown:

  • Li = Lithium

  • Fe = Iron

  • P = Phosphorus

  • O₄ = Four Oxygen atoms

So, LiFePO4 is the full molecular formula of the cathode material used in these batteries. Using “LiFePO” might still be understood in casual conversation or marketing, but if you’re being technically accurate—especially in writing or when sourcing batteries—you should stick with LiFePO4.

Want to see Lithium Batteries Tested, Torn Apart, and Discussed visit Will Prowse on Youtube 

Chargers for Lead Acid Starter Batteries and Deep Cycle Standard and AGM

Note:  Most of this was written in 2015.  I have verified all the manufacturer links are working and valid as of Spring 2025.  So while the model #’s may have changed some the quality and integrity of the information and companies have maintained their excellence over the past decade.

I personally own the CTEK Multi US 7002 which I purchased from Amazon (Was not available 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 option unavailable.  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 Battery Minder (Not to be confused with “Battery Tender”) I own the Battery Minder 11117, if it’s in your budget get the Battery Minder Model #201112 or newer replacement.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 Battery Minder 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.Manufacturer’s Website:  Battery Minders
  •  CTEK– The Models Multi US 3300 and Multi US 7002 are excellent chargers and on par with the VDC line up. CTEK also makes newer models specifically for lithium charging. Manufacturer’s Website: CTEK Battery Chargers
  • 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. Manufacturer’s Website:  Xantrex Batteries, Chargers, and Inverters.

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.

  1. Starter Batteries – designed for high cranking amps for a brief period of time and generally plain lead acid.
  2. Combination Starter/Deep Cycle Batteries – designed with both high cranking amps and a longer cycle life
  3. 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.

Lead Acid 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.