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Basil’s Garage

Reflections on Owning a 2020 Scamp 13’ for Five Years

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Reflections on Owning a 2020 Scamp 13’ for Five Years (Nov. 2024)

Note:  This is a follow up article to one written after two years of owning our Scamp

It’s already been five years since we took delivery of our new 2020 Scamp 13’ from the factory in November 2019!  It seems like just yesterday when the friendly Scamp driver pulled up to our house in San Diego after making the several day drive from Backus, Minnesota.  Since that time, we’ve taken 39 trips to 148 locations and have spent 266 nights in our Scamp!  To see complete articles on every trip we’ve taken, click here.  It now seems like a good time to reflect on our decision to buy our 2020 Scamp 13’ and what’s happened over the past five years.

We were very hesitant before purchasing our 2020 Scamp 13’.  We never had a travel trailer before, or even camped anywhere.  We were used to travelling, but did so by airplane and staying in spiffy hotels.  Before getting our Scamp, we had already travelled to six out of seven of the world’s continents (all but Antarctica) — but had hardly seen any places in the U.S. or Canada.  We figured that travelling by land would be a great way to see North America.  But, we weren’t sure if we would even like camping or towing a trailer.  We could have rented a used travel trailer to get some idea of what it’s like, but, instead, decided to go all in without a trial since it had been in our dreams for awhile.

At first, we did a lot of online research until we narrowed our choice to the Scamp and a few other models. We seriously considered other brands, including Airstream, TAB, and Safari Condo, before choosing Scamp.  And, we visited dealerships and spent a lot of time comparing models.  We even flew to Quebec City, Canada to visit the factory of Safari Condo!  For a detailed article on how we compared different trailers, click here.  We also visited a local Scamp owner who was referred to us by Scamp who owned a Scamp 16’.  She was very friendly and let us check out her trailer and told us stories about her adventures.

We ultimately chose Scamp due to its construction, features and size.  We wanted a fiberglass trailer because fiberglass trailers have a reputation of excellent quality and longevity generally not found in other trailer construction types.  We also desired a trailer we could fit in our garage and tow with our four cylinder car.  We did modify our garage height so we could have our Scamp at home (great for getting ready for trips) and not have to pay monthly storage fees or spend time driving to RV storage lots.  Click here to see how we raised our garage height from 7’ to 8’ to accommodate our Scamp 13’.  We learned that in California, trailers 16’ or shorter aren’t subject to yearly annual registration fees (it’s just an inexpensive permanent trailer plate fee every 5 years – currently $10), so getting a small trailer made good economic sense as well.

Our concerns about getting a travel trailer were quickly dissolved after taking delivery and experiencing our first couple of trips.  Although there was a learning curve, it wasn’t very steep.  When something didn’t work like we expected, we figured it out (sometimes by calling Scamp).  We also made good friends on trips and a few became excellent references for answering trailer questions.  Towing the trailer didn’t take much time to get used to (here are a couple of articles on our experiences towing and how we hitch up — towing and hitching up).  We learned a lot as we took more trips and rigorously documented our Scamp journey by blogging so others might benefit from our experiences.  Our Scamp blog not only lists all our trips, but also everything we have encountered along the way and all the modifications we have made on our Scamp 13’.

Having a small travel trailer has allowed us to travel considerably more often and more spontaneously than we would have if travelling by air / car / hotel.  It’s great being able to schedule a trip on a moment’s notice whenever we want.  Although campgrounds can be difficult to get into during peak months, we’ve always been successful at either booking last minute (if we didn’t make a reservation in advance) or finding alternatives.  And, it’s satisfying knowing that we will be sleeping in our own comfortable bed with our own clean bedding (and not having to be concerned about extra fees or hidden nightmares).  Additionally, the cost differences between taking a trip in our Scamp and reserving a hotel room are substantial.  Since we usually stay in State and National Parks, we generally don’t pay more than $40/night for a campsite (and, if you are 62 years old or older, National Parks and other federal lands, such as BLM & Forest Service parks, slash these costs in half if you buy a Lifetime Senior America the Beautiful Pass — currently $90 including fees).  A lot of campgrounds in the Eastern Sierra are run by the Forest Service and fees are generally around $32 / night (so, someone who has a Lifetime Senior America the Beautiful Pass would only pay 50%, or around $16/night at these campgrounds).

The average daily rate of a hotel room in the US was $148 in 2022 (Statista).  That’s at least a $100/night savings by travelling in a travel trailer versus staying in a hotel.  A simple calculation based on the 266 nights we’ve already stayed in our Scamp 13’ over the past five years shows we would have spent at least $39,368 (266 nights x $148/night average) for hotel rooms had we opted to stay in average priced hotels instead of buying our Scamp 13’ (which cost around $18K, including shipping)!!!  For an article on how we selected options and purchased our Scamp 13’, click here.  And, generally, prices for nice hotels in California are well north of $200/night.  And, hotels within National Parks (if they are available) tend to be very expensive.  For example, room rates at the Ahwanee Hotel in Yosemite National Park currently range between $578 and $1,347 per night.  Travelling in a small travel trailer brings other cost savings as well, such as not having to go out to eat for every meal.  We enjoy great home cooked meals in our Scamp for most days of our trips (although we do enjoy going out to eat occasionally).  Driving instead of flying plus renting a car can also be less expensive.

Over the past five years, we fortunately haven’t had any significant issues or maintenance costs with our 2020 Scamp 13’.  There have been some minor issues (e.g. replaced exterior door handle, bathroom door handle, hookup valve handletoilet spring cartridge kit, shower drain pump, and shower valve — all of which we installed ourselves), but nothing very expensive.  We take our Scamp 13’ to Sonrise RV every two years to have the bearings repacked and greased and the brakes adjusted (about $200).  And, we replaced the standard battery with a SOK 100ah lithium battery ourselves (now priced about $300) — click here to see how we did it.  We had a shop install a RedArc DC-DC battery charger (about $1,000) for fast charging of our Scamp’s lithium battery when we drive.  We have replaced the Scamp 13’ tires once ($50/tire) and plan to replace them every three years regardless of wear (see this article for more details).  We do most repairs ourselves, but a local shop could also easily do them for someone not wanting to do work on their trailer themselves.  We wax our Scamp 13’ every spring with our favorite marine wax.

Putting aside how doable buying and using a small travel trailer is and the potential huge cost savings small travel trailers provide compared to other types of travel, the main question for us when getting a travel trailer was “will this be fun?”.  Looking back over the past five years, the answer for us to this question is a resounding yes!  We have had so many outstanding adventures and met so many good friends during our travels, that getting our 2020 Scamp 13’ has been extremely fun and rewarding.  And, one of the biggest benefits of owning a small travel trailer is being able to stay in highly desired locations only possible by having one (such as inside a State or National Park).  We’ve been to so many beautiful areas with the closest hotel/motel lodging being thirty minutes or more drive away.  And, experiencing these places at night takes the park experience to another level (e.g. many animals come out at night and hearing and seeing them is fantastic!).  Plus, the quiet spent in nature once the day users leave is very special.  For anyone considering buying a small travel trailer, we would highly recommend the experience.  Owning a small travel trailer might change your life for the better!

 

Disclaimer:  You will get the same great Amazon price by clicking on the links here compared to buying directly on Amazon, but by buying here you will also be supporting the continuation of this website as we get a small commission from each sale.  These are products and procedures we use for our own Scamp that we selected and developed from our own research and experiences.  However, we do not endorse any specific product and cannot guarantee that the products we use are exemplary and the procedures we use are complete, accurate, detail the correct recommended procedures, or apply to your model small travel trailer.  It’s always best to double check with your manufacturer or operation manuals to ensure you are doing everything

Why & How I Easily Converted My Scamp Travel Trailer from a Lead Acid to Lithium Battery

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Why & How I Easily Converted My Scamp Travel Trailer from a Lead Acid to Lithium Battery

Why Switch?  The Benefits of Lithium Batteries
Our 2020 Scamp 13’ came with a wet lead acid battery (Northern brand Group 27 – est. capacity 67 -100 amp-hours) which was manufactured in June 2019.  [Note:  the term amp-hours (Ah) is a measure of battery capacity.  For example, a 100Ah 12-volt lithium battery can provide 100 amps to a 12-volt 100 amp device for one hour (after which time the battery would be completely depleted).  The same 100Ah battery could supply power for 4 hours to a 25 amp device (100/25=4).].  We find we use about 12 amp-hours per day (running LED lights, pumps, etc.) when boondocking (no electrical hookup), giving us about 8 days of power (100/12=8.3 days) if we don’t use any source to recharge the battery.

The lead acid battery is considered “wet” because it has liquid solution (battery acid) and requires monitoring levels.  If the liquid levels get too low, the battery can be damaged.  So, periodically, the plastic caps have to be opened on the top of the battery and distilled water added (other maintenance is also recommended on occasion such as periodic equalization and checking electrolytes – but, who does this?!!!).  These batteries can also off-gas hydrogen when charging, so they need to be vented to release the fumes (on a travel trailer, this means they are mounted outside on the trailer’s tongue).  The average lifespan of a lead acid battery is 3 – 5 years but can vary depending on the manufacturing process, the care it receives, and the conditions in which it operates (e.g. extreme heat may greatly reduce the life of the battery).  The figure of 1,000 charging cycles is often cited by manufacturers for this type of battery.

Our Scamp’s lead acid battery had served us adequately, although its limitations were apparent since day one.  First, lead acid batteries should not be discharged more than 50% (about 12.0V) or irreversible damage may occur.  So, effectively, only half of the lead acid battery’s capacity can be used (so the 100ah battery is equivalent to about 50ah)!  We needed to closely monitor the Scamp battery when using multiple appliances at night to make sure the voltage didn’t drop below 12.0 volts for too long. We spend a lot of time boondocking (without electric hookups) and the battery ran down fairly quickly (within two to three days of use running our LED lights, fan, water pump, shower pump, furnace, etc.).  Our 100 watt solar panels, though, had saved us on many occasions when hookups weren’t available by allowing us to charge the battery during the day in good weather.  The Scamp’s lead acid battery also had to be maintained periodically by filling it with distilled water (when levels were low).  Fortunately, our friend Phil helped us test and maintain the battery using distilled water and a kit to test electrolytes.

Our Scamp’s 2019 lead acid battery began to show its age this year.  At about four years old, it was nearing the end of the average lifespan for this type of battery.  We noticed that the full charge didn’t seem to last quite as long.  Instead of trying to milk it for a few more years, we decided it was time for a change.  We planned the switch to a lithium battery ahead of a big trip to the coastal California redwoods – knowing there would be long periods without electric hookups (under densely shaded heavy foliage in the forest which would limit solar charging).  Not wanting to deal with lead acid batteries any longer (or battery issues on our trip), I extensively researched lithium batteries.  The first thing I discovered is that modern RV lithium battery chemistry, LiFePO4 (lithium iron phosphate), is considered very safe (said to be the safest of the lithium battery types) and unlikely to catch fire (very different than other types).  They have a very low risk of overheating and catching fire due to their more stable cathode material and lower operating temperatures.  Additional benefits over lead acid batteries include increased capacity (about double lead acid batteries), faster charging (4 x faster), reduced weight (about ½ the weight), and longer lifetime (10 years or more — 2 to 3 times lead acid battery average lifespan).  Additionally, high quality LiFePO4 batteries have a built in BMS (battery management system) that protects the battery from overcharge, over-discharge, and short circuits.  Some even have a temperature controller to shut down charging when temperatures dip below freezing (which can damage LiFePO4 batteries).  After learning about these additional benefits in lithium battery chemistry, I was really motived to keep researching.

Trailer Converter & Wiring Compatibility
Before purchasing a lithium battery, I wanted to verify that I would be able to charge it safely with the Scamp’s Progressive Dynamics 45 amp 9245C converter (converts AC to DC 12V when hooked up to an AC outlet to run the Scamp 12V appliances, like lighting, and charging the Scamp battery) running through the trailer’s existing wiring (I was told by Scamp they used 12-gauge wire on 2020 models).  LiFePO4 lithium batteries generally require a charging voltage between 14.4 – 14.6V (higher than lead acid batteries).  So, the converter needs to be able to output this voltage for sufficient charging.  SOK Battery recommends 20 – 40 amps charging current (i.e. charging a 100ah battery at 20 amps will take it from 0 to 100% in five hours – very fast). However, I wasn’t too concerned about getting this many amps to the battery to charge it quickly because we generally stay at the campground at least 24 hours – so, slower charging would be acceptable.  So, the main questions I had were if the 12-gauge wire (rated for 20 amps — and there is a 20 amp fuse on the positive converter connection at the Scamp battery) would handle the current output by the 45 amp converter going to the battery (wouldn’t blow the 20 amp fuse at the battery) and if the converter could output a minimum of 14.4V.

I called Progressive Dynamics and spoke to a tech.  He told me that the PD9245C converter that our Scamp 13’ came with can charge lithium batteries with the optional pendant (sold separately here).  It’s a little box that plugs into the converter (less than $15 at the time I purchased) and has a button which allows the converter to output 14.4 volts in Boost mode (for four hours at a time when its button is pushed).  Otherwise, the converter won’t get up to the required minimum voltage (14.4V) to fully charge lithium batteries.  He also said that whatever current isn’t used in the trailer will be sent to the battery (potentially up to almost 45 amps!).  So, he strongly recommended changing the existing wiring going from the converter to the fuse box to the battery (both positive and negative wires) to 6-gauge wire.  He said that the 20 amp fuse at the battery would likely blow often if this wasn’t done.  Because our Scamp 13’ has a bathroom and the wires run behind it, the job would involve running the wire up to the refrigerator area in the front of the Scamp and then cutting a hole in the floor and running it under the front part of the trailer up to the battery.  I took a look under the bench seat where the converter is mounted and followed the wiring to the fuse box next to it (and removed the fuse box from the wall to look closely at the wiring) and then onto the side of the trailer by opening the side refrigerator panel.  From there, the wiring goes into the wall behind the bathroom and comes out the front of the Scamp through the front closet floor.  This didn’t seem like too difficult a job, so I ordered the copper 6-gauge wires, battery lugs, brackets, etc. ($271 altogether on Amazon at the time of my order).  Fortunately, all of the supplies I ordered were returnable, because, as you will read below, I ended up not using them!

Choosing A Brand
Once convinced our next Scamp battery would be a LifePo4 lithium battery, I shopped brands (and there are a ton of choices) and watched YouTube videos of experts taking apart these batteries to conduct extensive analysis on them to help distinguish between the high quality from the numerous poor quality batteries.  Here’s one such video that reviews a variety of Chinese brands.  After a couple of weeks of this type of research, I was able to identify some of the highest quality US and Chinese brands of LiFePO4 batteries.  I also called battery distributors carrying the best US and Chinese brands and asked about build quality and return rates between the batteries.  What I learned was that one of the leading Chinese made batteries, SOK Battery, is comparable in quality and return rates to one of the leading US brands but costing about half the price.  After doing this research, I purchased a 100ah SOK marine battery which has a battery management system (BMS, including low temperature charging shut-off) and Bluetooth.  This battery fits perfectly within the Group 27 plastic battery box that came with our Scamp 13’and sits outside at the front of the trailer near the hitch.  Many of the batteries I researched (including other SOK batteries) were too big to fit inside our existing battery box.  I ordered a marine battery version (water tight enclosure) because, although the battery goes inside a plastic battery box, the battery/battery box sits outside on the trailer’s tongue and is exposed to the elements.

I ordered the SOK 100ah marine battery with BMS and Bluetooth directly from the manufacturer’s website here, priced at $500 (free shipping) at the time of this article (in comparison, a decent new sealed 100ah AGM battery – an advance type of lead acid battery — cost between $200 and $300).  The SOK battery comes with a 7-year manufacturer warranty.  SOK ships to US customers from their US warehouse and I received the battery, which was well packaged in protective Styrofoam, in about five days.  The SOK marine battery is super clean looking in a nicely sealed black plastic case.  I weighed both the old lead acid battery (48 lbs.) and the new SOK battery (24 lbs.) and was pleased how easy it is to lift the new SOK battery.

Installation and Configuration
The SOK battery fits perfectly into the Scamp’s existing plastic Group 27 battery box, taking up about the same amount of space as the old lead acid battery.  It was easy attaching all the battery connectors from the Scamp’s various systems (e.g. converter, brake, electric jack, etc.) to the SOK battery terminals because I was careful to label each wire (and indicate which was positive and negative) before removing the wires from the old battery.  I downloaded the ABC-BMS app to my Android phone, opened it, and it did not connect to the SOK battery.  I guessed the battery was in a deep sleep after being shipped from China, so I plugged the Scamp into the AC wall outlet and the app quickly connected.  Note:  the battery also goes to sleep every six hours without use.  Simply turn on the shower floor water pump or other appliance that has significant current draw and the battery will wake up and the app will then connect.  Another way to wake up the battery is to plug in the trailer to shore power (and perhaps press the button on the Wizard pendant to get the voltage up over 14v).

I initially liked the app because it not only shows State of Charge (SOC) of the battery in percentage but also a lot of other really useful data.  One extremely helpful piece of information on the app is the current flow (amp) into and out of the battery.  I relied on this extensively when testing the new lithium SOK battery and it allowed me to forgo rewiring the Scamp because I saw that the current flow to the battery when charging was never over 20 amps (the rating for the circuit breaker at the battery).  Eventually, though, I grew tired of having to wake up the battery to get the app to work and I also found the SOC value to become inaccurate when the Scamp was sitting for long periods in the garage.  The voltage would continue to drop over a couple of weeks, but the SOK app would still show 100% SOC.  The app fails to register small parasitic loads from appliances when calculating the SOC (which quietly drain the battery over time just by being plugged in, even when all accessories are off).  I contacted SOK and they advised that an external shunt would be much more accurate than the internal BMS for measuring SOC.  In turn, I purchased a Victron SmartShunt which is extremely accurate and works whether or not the battery is sleeping.  The external smart shunt, which sits between the lithium battery negative terminal and all negative loads, very accurately calculates SOC by effectively measuring all the current going out of the battery.  The Victron SmartShunt app shows that my Scamp has a drain of about .14 A when sitting in storage in the garage.  Here’s a video I made showing much more detail on how the Victron SmartShunt is installed and set up.

Victron calibration guide:  click here.

Testing New Battery
The first thing I did after installing the new SOK battery was plug in the Scamp to the AC wall outlet to see if I would need to change out the trailer’s existing 12 gauge wire.  The battery arrived at 60% SOC and I intended to charge it to 100% while carefully monitoring the amps received at the battery using the SOK app (after putting the converter into 14.4V Boost mode, by pressing the button on the pendant).  Without any electric appliances running in the Scamp, the SOK app showed 9 to 10 amps going into the battery from the converter (so nothing like the high number of amps the Progressive Dynamics tech warned about).  At 10 amps, the 100ah battery charges at about 10% per hour and would take 10 hours at this current to go from 0 to 100% charge.  Since the SOK battery was already at 60% SOC, it only took about 4 hours to charge to 100%.  During the charging process, I periodically felt the + and – converter wires at the battery.  They remained cool the entire time, the 20 amp fuse never blew, and the charging current never exceeded 10 amps (far below the 20amp rating of the existing 12 gauge wire on the Scamp).  I also tested the current from the 7-pin connector plugged into our Volvo XC40 tow vehicle when the SOK battery was at 82% SOC.  With the ignition off, the app showed no power coming or going from the SOK battery.  With the car running, the app showed the SOK battery receiving 4 amps from the 7 pin connector.

Because lithium batteries take more current and charge faster when they are at a lower state of charge (Ohm’s law:  Current (amps) = Voltage [voltage charging – voltage battery] / Resistance), I decided to run some additional experiments with the SOK battery at a much lower SOC.  I used the three way refrigerator in 12 volt mode to deplete the battery (at 82%) down to 20% SOC (it took about 6 hours to do this since the 12V refrigerator uses around 10 amps).  As expected, the charging current rates when the SOK battery was at 20% SOC were significantly higher than previous tests at 82% SOC.  But, were they high enough to heat up the wiring and blow the converter wiring’s 20 amp fuse at the battery terminal?  Fortunately, they were not.  With the Volvo XC40 plugged into the Scamp via the 7-pin connector, the SOK battery received between 8 – 10 amps when the car was running (no amps when the car was off) compared to only 4 amps previously when the SOK battery was at 82% SOC.  When the Scamp was plugged into the AC outlet, the SOK battery received between 14-16 amps.  As the SOK battery charged, the current rate fell back down to around 10 amps (at 45% SOC).  So, it seems the battery follows Ohm’s law and gets noticeably hungrier and draws in higher current when charging at very low state of charge (less than 30%).  But, even so, the wires remained cool the entire time, and the 20 amp fuse never blew (keeping below the 20amp rating of the existing 12-gauge wire on the Scamp 13’).

Charging Scenarios
There are at least four ways to keep a lithium battery charged when travelling.

  1. Electrical Hookup
  2. Solar Panels (optional)
  3. 7-pin car charging
  4. DC-DC Car Charging (optional)

Each of these methods is discussed below.

Real World Testing –20 Day California Coastal Redwoods – Oregon Adventure
As testing predicted, our Scamp’s existing 12-gauge wiring did work well for charging with the converter when staying at campsites with an electrical hookup and also with the 7-pin connector while driving.  But, a big question was whether the 100ah SOK battery would be sufficiently charged for our style of camping.  In other words, would the mix of our camping between campgrounds with and without electrical hookups (with solar panels when there was sunshine) and driving distances (charging with the 7 pin connector and running our 12 volt refrigerator while driving) be sufficient to keep our 100ah SOK battery charged on long trips?  Since we often spend long periods of time (up to a week) boondocking (no electric hookup – at one or multiple locations) and only periodically stay at campgrounds with electrical hookups, considering all forms of charging seemed like a good idea.  Fortunately, our recent twenty day trip up the California coast into the redwoods and beyond into Oregon offered a mix of different types of camping, providing perfect testing conditions for our lithium battery and insight into the best ways to keep it charged for our travelling style.

We travelled with the Scamp’s 12V refrigerator running to test the actual draw on the SOK battery while driving since the goal is to keep refrigerated food cold without having to run propane (we don’t want to take the safety risk of running the refrigerator from propane while driving and also the inconvenience of having to turn the propane off before entering gas stations).  We found that running the refrigerator while driving consistently depleted the SOK battery at about 10% of charge capacity per hour.  So, for example, when we left a campground with our SOK battery at 100% charge and drove four hours we would arrive with our battery at 60% SOC.  Fortunately, we had no issues on this trip because we used our solar panels to charge up at most campsites after arriving.  However, we decided to add a DC-DC car charger (see below) after this trip so we can run the refrigerator and charge our SOK battery at the same time while driving.

1.  Electrical hookup
Using shore power (AC outlet) is the simplest way to charge a lithium battery.  When the trailer is plugged into an AC electrical hookup, the trailer’s converter will provide around 14.4 volts power to charge the battery (as discussed previously, our converter required an add on “wizard” pendant to increase the voltage to 14.4 volts which is required for charging lithium batteries).  Standard (“non-lithium”) converters will not be capable of fully charging a lithium battery, so it’s important to research what converter is in your trailer and either replace it or upgrade it (like we did) if necessary so that it is capable of charging the new lithium battery.  Our 100ah SOK lithium battery charges at about 10% per hour when plugged into an AC outlet (mostly while in “boost mode”, which is when the pendant button is pushed on the “wizard” and the voltage is increased to 14.4 volts).  The SOK battery charged well at campgrounds with hookups.  We found our battery fully charged every morning on our recent trip.

2.  Solar Panels
We have a 100 watt solar briefcase which we had been using successfully to charge our old lead acid battery at campgrounds without hookups.  The panels are capable of supplying up to 8 amps (100 watts/12 volts, from the formula amps x volts = watts) of power.  So, on a sunny day, with eight hours of good sun, the panels could possibly provide the 100ah SOK battery up to 64ah of capacity (8 amps x 8 hours) or 64% of the total battery capacity!  Because we usually have good weather when camping (i.e. good solar charging conditions) and estimate our daily battery use at around 12Ah or less, the solar panel solution seemed like it would work great for the lithium battery.  The only change we made was replacing the existing inexpensive solar charge controller to one that has a LiFePO4 setting.  The solar charge controller sits between the solar panels and the battery and regulates the charge states so the battery is safely and properly charged.

We opted to purchase a high end charge controller since we are charging an expensive LiFePO4 battery with double the useable capacity (and ½ the weight) as our old lead acid battery.  This Victron Energy smart controller features MPPT technology (as opposed to the PWM technology that basic controllers have) with a long five year warranty.  Without getting into a lot of detail, MPPT is widely recognized as more efficient (up to 30% more efficient) than PWM technology, which generally means higher amps collected from the panels and sent to the battery (faster battery charging times).  The downside of MPPT controllers is that they are generally much more expensive and complex than PWM controllers.  The PWM controller we used for our Scamp’s original lead acid battery was only $16 on Amazon and seemed to do a good job charging it (although not compatible with LiFePO4 batteries).  However, because we wanted to make sure the much more expensive SOK battery is safely and efficiently charged, we decided to spend more ($112 at the time of this article) on the Victron smart controller which is compatible with LiFePO4 batteries.  Having the extra charging efficiency is helpful because there is more battery capacity to replenish with a lithium battery compared to a lead acid battery.  This is because a comparable lead acid battery should only be allowed to run down to about 50% capacity or 12 volts whereas a 100ah lithium battery can be safely discharged to a much lower SOC — some manufacturers say safely to 0%, others 10-20%.

The Victron Energy SmartSolar MPPT 75V 15 amp 12/24 volt solar charge controller with Bluetooth arrived quickly after ordering from Amazon and was easy to install.  I removed the old controller (which I had attached to the back of the solar panels with Scotch extreme fastener tape), screwed down both the positive and negative wires from the panels and the battery leads into the new Victron controller (being careful to make sure the red positive wires and black negative wires went into their respective slots), and used extreme fastener tape to secure the controller to the back of the panels.  Fortunately, the thickness of the new Victron controller was thin enough to allow the panels to fully fold up into a briefcase and lock.  To program, I opened up the panels inside my house and exposed them to some outdoor light to power the controller (the panels were not connected to a battery).  I used my mobile phone’s reader app to scan the QR code on the controller, which opened up the Victron app page on the Google Play store to download.  Downloading the Victron app was fairly quick and it required a couple of updates after downloading.  The only thing I adjusted in the settings was for the battery type, LiFePO4, which sets the parameters for this type of lithium battery.  After the quick setup, I took the panels outside and connected them to the Scamp.  All the information shown on the Victron app is amazing.  The app shows voltage generated by the panels and the regulated voltage and current going into the battery.  There are also graphs that can be generated showing a variety of different parameters.  It was interesting comparing the Victron data against the SOK battery data in real time, which, it turns out, were very similar.  For example, the current and voltage coming from the panels as displayed on the Victron app was very similar to the current and voltage going into the battery shown on the SOK app.

The solar panels coupled with the Victron controller did a great job recharging our SOK 100ah lithium battery on our recent trip.  We often arrived at campgrounds without hookups with our lithium battery depleted to between 60% and 80% SOC as a result of running the 12v refrigerator.  In most cases, placing the solar panels out in the sun resulted into a full charge to our SOK battery in less than 6 hours.  Under partly cloudy to sunny skies, the panels usually output between 6 to 7 amps per hour to the SOK battery.  The panels didn’t produce much if any electricity at all under heavy cloudy skies or no sun conditions (like we experienced in the dense redwoods forests).  In these cases, the DC-DC charging scenario of charging comes into relevance (see below).

 3.  7-pin car charging
Connecting the travel trailer to the tow vehicle with the 7-pin connector not only allows the trailer’s tail lights to mimic the tow vehicle’s signal lights (e.g. turn signals, brake lights) and control the electronic brakes, power can also pass through it between the tow vehicle and trailer.  On our twenty day trip to the California redwoods and Oregon, the power flow was usually around 4 amps from the tow vehicle into the Scamp lithium battery.  However, on some occasions, the flow was actually negative, with power going from the Scamp battery back to the tow vehicle’s battery.  Current usually flows from high voltage to low voltage (known as “potential”), so when the travel trailer battery has a higher charge than the tow vehicle, current may transfer from the trailer battery to the tow vehicle battery.   Since we like running our 12V refrigerator while driving, we found that even with the 7-pin connector providing some power, our new SOK lithium battery usually loses about 6 to 10 amps of capacity per hour while driving.  So, after a typical four hour drive with our 12v refrigerator running, our SOK lithium battery state of charge (SOC) would often be around 60% (when starting at 100% SOC).  The bottom line is that the 7-pin connector cannot be relied on to charge the trailer battery while driving as it puts out very little current for this purpose.

4.  DC-DC Car Charging, “The Game Changer”
We chose to install a DC-DC car charger so we could drive with our 12 volt refrigerator running without depleting our 100ah SOK lithium battery.  It allows the tow vehicle (assuming the tow vehicle’s alternator can output enough amps) to charge the trailer battery at a very fast rate.  Heavy gage cable (6 gage cable in this case) is run from the tow vehicle battery (hidden under the cars body panels) to Anderson SB50 quick connectors at the back of the tow vehicle.  The DC-DC charger is installed next to the travel trailer battery.  The DC-DC charger takes power generated by the tow vehicle’s alternator and regulates the voltage up to a certain amount (just over 40 amps in this case).

Without the DC-DC car charger, our lithium battery generally is depleted by about 10 amps or 10% of its charge per hour when driving with our 12 volt refrigerator running (as mentioned above).  In many cases, we can make up this shortfall in capacity by using our solar panels at the new campground.  However, in some circumstances (like we experienced in the dense foliage of the redwoods on our last trip) arriving with 100% SOC is a better plan (especially if staying for a long period of time).  Bad weather (e.g. windy, rainy, heavy clouds, etc.) or being in a sketchy environment (where risk of solar panel theft might be high) may also throw a wrench in charging plans, sidelining the use of solar panels.  So, after reviewing experiences from our recent twenty day trip we decided integrating a DC-DC car charger would be desirable for how we travel.  The DC-DC car charger gives us peace of mind, ensuring that our lithium battery will be fully charged when we arrive at the campground (even when running our 12V refrigerator).

We did a lot of research and purchased a RedArc 40amp DC-DC car charger (RedArc BCDC1240D) with the RedArc 60A Fuse Kit (FK60).  RedArc is one of the highest regarded manufacturers of these chargers and makes some very powerful ones (like 40 amp and 50 amp versions).  A 50 amp DC-DC car charger can charge a 100ah battery in about two hours of driving!  This brand is one of the most expensive (and based on our experience worth it!), but there are also other brands (such as this Renogy 40 amp DC-DC charger) which may do a good job.   We chose a local company, Basil’s Garage, to install the charger as it requires removing body panels within the tow vehicle and installing heavy gage wiring from the engine compartment within underbody panel compartments to the back of the tow vehicle (installation was about $500 and took about 3 hours).  The techs at Basil’s Garage are excellent and really know their trade.  Additionally, a cable is needed to the tow vehicle’s fuse box to keep the DC-DC charger from stopping when the smart alternator drops the voltage to save power.  After the installation, the SOK app showed 42 amps going into the battery (vs. about 4 amps from the 7-pin connector when the DC-DC connector was disconnected).  And, after turning on the 12V refrigerator, the SOK app showed 32 amps still going into the SOK battery with the tow vehicle running!   We put our new DC-DC car charger to the test with a trip up the coast to several beach campgrounds (see trip report here).  Indeed, the DC-DC charger worked wonderfully during our trip supplying our Scamp’s lithium battery up to 32 amps of power when needed while powering our 12 volt refrigerator at the same time.  The system worked so well that we didn’t even need to use our solar panels (we arrived at each campground with cold refrigerated food and our lithium battery SOC at 100%)!  We consider DC-DC charging a real “game changer”.

Final Thoughts
Now that the price of high quality LiFeP04 batteries for travel trailers has come down to more reasonable levels, it seems like a no brainer to swap out a trailer’s lead acid battery for a LiFePO4 lithium battery.  For just two to three hundred dollars more, one can buy a lithium battery that compared to a lead acid battery is ½ the weight, gives 2x the capacity, doesn’t off gas hydrogen, doesn’t require maintenance, lasts 10 years or more (2 to 3 times lead acid battery average lifespans) and charges much faster.  Additionally, the LiFeP04 battery in a travel trailer sitting in storage can sit a lot longer without getting depleted by parasitic loads from appliances due to higher useable capacity.  This can mean fewer trips to the storage facility to charge the battery.  Lastly, there are a lot of great optional methods (e.g. AC hookup, solar panels, and DC-DC charger) available to quickly charge up a travel trailers LiFePO4 battery when travelling.  And, because LiFePO4 batteries charge much faster, there’s a better chance of having battery capacity when it is needed!

Disclaimer:  You will get the same great Amazon price by clicking on the links here compared to buying directly on Amazon, but by buying here you will also be supporting the continuation of this website as we get a small commission from each sale.  These are products and procedures we use for our own Scamp that we selected and developed from our own research and experiences.  However, we do not endorse any specific product and cannot guarantee that the products we use are exemplary and the procedures we use are complete, accurate, detail the correct recommended procedures, or apply to your model small travel trailer.  It’s always best to double check with your manufacturer or operation manuals to ensure you are doing everything correctly.