More Yosemite

More from our West Coast trek.

Tenaya Lake

Ah, The Carefree RV Lifestyle

As the winter recedes we begin planning for the milder weather. I have had the opportunity to read some of the blogs, websites and articles which promote full time RVing. Those that promote a nomadic existence are interesting.  This seems attractive; they suggest that we follow the mild weather and keep living costs low. Some promote boondocking (living on public lands for next to nothing), using free solar power and living a modest lifestyle. Sounds great; in particular that "modest lifestyle" which is what I do practice. But as someone involved in my community and who does own residential real estate, and as someone who has raised children,  I do have some questions and concerns.

First and foremost, if I choose to live the carefree RV lifestyle, then who pays for infrastructure? A lot of this comes from property and municipal taxes. Furthermore, in most communities the entire public school system is supported via real estate taxes. Living on the cheap on public lands turns over the financial support and burden to others. While this might be a good thing for the few, it poses problems. The financial burden falls upon the remaining who provide that infrastructure to the few.

Living a nomadic, RV lifestyle implies that I will only pay consumer taxes; mostly sales tax on my purchases and Federal taxes on any gas or diesel I purchase. Unfortunately, these don't cover the entire bill of supporting the infrastructure and benefits of a modern society. While it can be argued that the RVer doesn't use or require some of the things provided by modern society, I find that to be hollow. We need food, fresh water, a health care system, roads, electricity, gasoline or diesel, and propane. We do need to dump those tanks and that implies a water treatment system; for those with a septic system, the question is "how and with what materials was it built?" I doubt it was dug by hand. Ditto for anyone who says "I have a well for fresh water."

That RV and the solar panels, electrical and electronic systems, batteries, wi-fi system, GPS, cellphone, appliances, satellite TV system, personal computers, etc. had to be built somewhere and with a lot of technology. It takes an entire infrastructure system and millions of people to put the entire thing together and the system it is plugged into. The food we eat requires water, chemicals, seeds, pesticides and so on. Yes, I know, we can purchase organic. What about that container the milk comes in? Some will say we can and should adhere to organic and the world will be a better place. False. Most of us would starve if we were forced to only purchase organic goods. Most of us could never eat salmon. Etc. Etc. Etc. Most of the people I know don't want to subsist on the diet available to the typical Chinese in 1950. Nor do we want to live on the mush diet that was concocted in the 1970s for societies which can't afford more than a few hundred dollars a year for food.  So what is really being promoted here?

In other words, I am of the opinion that pretending I am "living off the land" in my RV is a pipe dream. The first time I pull into a gas station I prove that to be a fiction. Ditto if I ever plug my RV into a 30A or 50A electrical receptacle, or to a fresh water spigot or use a dump station. In fact, about 45% of the electricity east of the Mississippi is derived from fossil and nuclear power plants. In other words, electricity from so called "dirty, belching and carbon polluting sources of energy." My dream existence is supported by an extensive industrial infrastructure.  If whatever I am using was produced in China the reality is much worse.

Health care has made this interesting. Obamacare shifted the landscape in health care for the carefree RVer. Prior to Obamacare aka "The Affordable Health Care Act." it was purely optional to have any health insurance. If something happened, one could go to a health clinic or hospital to get medical aid. With no, or minimal means of support or income, it would be easy to qualify for a variety of free, public supported aids. Now, anyone with a means of support is required to obtain health insurance, or pay a penalty.  However, all one has to do is Bing or Google "getting free healthcare" and the list will appear. According to Google, there are 243 million results.

The concept of a carefree RV lifestyle is reminiscent of the wonders of the all electric vehicles. It might be too good to be true, or perhaps only palatable if I ignore some of the consequences. For example, electric vehicles were promoted, for a time, as "zero emission" vehicles. Nothing could have been further from the truth. Today the marketing is "zero tailpipe emissions." That's an improvement as it is merely deceptive. As I mentioned earlier in this post, about 45% of the electric power east of the Mississippi is derived from fossil fuels and nuclear power plants. For a time California had a deal with states to the east to build electric generating plants so California could avoid having these on California soil. That's how California was able to promote itself as a "clean energy" state.

The fact is, the roads all automobiles are driven upon are maintained in part via taxes on diesel and gasoline fuels. Electric vehicles have been given a pass by the politicians and generous subsidies, paid by the rest of us. At my HOA we've even had a few attempt to charge their electric vehicles using HOA paid electricity. When I argued this was the equivalent of free gas paid for by the fees of other owners, a few rallied to the defense of the electrics. Common sense prevailed, because in our HOA the rest of us don't want higher fees. As is so, so true, an idea is frequently a "good idea" until it has to be paid for.

Perhaps a better title for this post would have been "living the dream" at the expense of others. I have concluded that a dream is all that it is. I suspect this is another one of those ideas that is "too good to be true." I take the perspective "if we all lived this way, what would be the outcome?" It's apparent that schools would be unfunded, most municipalities would be gutted like Detroit.

But I'd be having fun on Bureau of Land Management property. Only when I had to go off the reservation would I have to deal with reality.

However, the idea has merit. What is necessary is to balance personal wants, needs and desires with the needs of society. Come to think of it, this it true for all of us, whether we live in an apartment, condominium, home or RV. Isn't it?

Wild Mustangs

One of the opportunities when travelling in the western US is to get up close with mustangs. The mustang is a descendant of the Spanish horses from the Iberian peninsula. These horses were brought to the continent by Spanish explorers in the 16th century. These horses have bred over the centuries with other types and roam wild in portions of the American southwest.

There are a number of organizations that care for these animals and perform "rescue" functions. It's possible to get up close to these animals. We did so on a trek. They are very inquisitive, but skittish. It's best to "ease into" their space and give them an opportunity to get comfortable.

After a while they'll check you out. If you are ticklish it can be stimulating.

They like to be led and will follow you when they become comfortable. 

There will always be a few onlookers to see how you are doing and observe what's going on.

Mustangs love to run; all that is required is an excuse.

We can all get into the act.

Everyone had a good time.

More on our 2392 mile trek - Yosemite

On this particular trek, I took on average about one photo every two miles. We assembled the best 516 photos into a slide show, put them to music and sent them to the guests we took on this trip, as a memento.

This particular trek required three months of planning on my part. At the time I told G that this would be "the trip of a lifetime." She doubted this, but after and on reviewing the many photos and videos she said "It was!"

Now, for those living in their RVs full time, this might be normal. However, I challenge the reader to consider that if life is a journey, and for each of us I do assert that is so, then each and every day is one in  our personal "trip of a lifetime."

The Tools

We have the internet and that is useful. I used Microsoft "Streets and Trips" as a planning tool. That software included a GPS dongle and real time updates. Unfortunately, MS has suspended this software and will only continue "mainstream support" until July 14, 2015.

MS is promoting "Bing.com/maps" as their replacement. Not even close in my opinion. Ditto for Google Maps.

On this particular trek, there were times cellphone coverage was nonexistent. Try to access the internet when your cellphone is down. The version of MS streets that I use performed flawlessly during this trek because it doesn't matter where one is, it is always possible to get line of sight to the necessary GPS satellites. My maps had been previously constructed on my PC. So I didn't require a cellphone connection.

A Yosemite meadow:

On the trail with family walking toward the El Capitan Bridge:

Near the "Four Mile Trail":

MS Streets & Trips Real Time view on my PC (via GPS)

RV Trekking when the temperatures drop

Updated after some reflection. See the comment at the end of this post. This post isn't about summer in Yosemite. This dragonfly is on the masthead accompanying this post. However, this particular post is about winter.

I think we've enjoyed our winter treks, during which temperature ranges we experienced while living in our camper van were from 2F to 79F. That's quite a difference and being prepared for this is essential. On our first experience in a RV we encountered fall nighttime temperatures of 20F. That experience gave us some first hand knowledge about cold weather comfort in an all-electric RV (solar/batteries/shore power). Our first winter trek was in early December, 2013 and we left for warmer climes in a stock RT with blankets, a 1500 watt supplemental electric heater and a roll of Reflectix. We learned a lot on that trek and we've applied what we have learned. This January we were much more comfortable during our second winter trek.

December 2013 - First Winter Trek

This isn't one of those posts about the joys of living in my RV and off the grid when the outside temperature outside is 20F or lower. Nor am I going to post about how we should get arctic gear and a balaclava to help us get through our winter RVing experience. If you are doing that, then I am sure you are practicing all the tips in this blog and more.

Yes, it is possible to RV in really nasty winter conditions. I've also ground camped at temperatures down to -25F and experienced and worked in temperatures to -65F wind chills. This blog is not about winter survival RVing. I do want to travel in comfort and I do want to be prepared for problems and issues. My spouse is most appreciative.

Almost Ready to Roll, 9 F at 7:30am

Let's be real, shall we. Many RVers use their home on wheels during the winter months for the purpose of escaping the ravages of winter. That is, after all, one of the reasons to have a home on wheels; we can get away! Others use them only in the fall, summer and in spring. When the climate gets ugly, we simply retreat to our wooden homes, or if in the RV, we move a few hundred miles and choose a better (warmer) location. There are numerous personal RV websites out there and you may notice some authors spend a lot of time during the winter travelling west to east, from San Diego, California to Florida and back. That's with good reason. It's to keep above 45F. However, if we travel anytime other than summer or more extensively northward we will each eventually encounter cold weather and we'll have to deal with below freezing temperatures. That is what this particular post is about. There are things we can do to be prepared and to make winter cold weather RVing more enjoyable.

These are my experiences as a RV newbie and some tips. I call them "rules" but you might prefer "aids" or "tips."

Now, if you are reading this from an all solar RV in southern Arizona, then this blog isn't for you. This post is provided to share my experiences in a small RV which has propane and gasoline generator when disconnected from "shore power" and two 6V AGM batteries. During the winter months if we are in our RV,  we spend most of our time connected to shore power, unless we are in movement, and we move frequently. We have not yet stayed in one location more than 10 days. We chose this particular RV because we wanted the ability to experience true 3.5 season RVing from Michigan to Arizona and with few restrictions. If you are of similar interest, then this post is for you.

We prefer to travel when the temperatures are above freezing during the daylight hours. However, nature doesn't always agree with our desires and nor does our schedule. In January we took a trek and escaped most of the cold weather here in the Northland. But darn, a more southerly storm from the west coast brought snow and cold. The nighttime temperature in Roswell, NM fell to 5F. That was an inconvenience as I had to re-winterize the RT before the temperatures dropped. (I recorded a low of 2F that night and early morning).

There are a lot of things to be said about this, but the primary issues are to have adequate fuel, be prepared and have what it takes for comfort. Our personalized and improved Roadtrek 210P has what it takes.

Rule #1:  Be very familiar with your RV's winterization requirement and winter limitations. I can't stress this enough. Be prepared to dump tanks, add anti-freeze and so on if you are trekking anywhere that below freezing weather is even a remote possibility, Yes, one or more of your fresh water tanks may be in a heated area. But what do you do if the heat fails? I recommend we be prepared. We've had a propane regulator failure, twitchy AGM batteries and a generator that didn't want to start (after some coaxing and patience it did start).

Rule #2. If travelling in the winter, spring or fall, be prepared for freezing weather.

During our January trek, we began at 30F and became complacent when daytime temperatures reached 50F. However, a winter storm dropped temperatures in the Roswell, NM area to 2F.  We had blankets for sleeping and a supplemental electric heater and full propane for the furnace, so we were adequately warm at night. We also had winter clothing and an adequate supply of "pink" antifreeze. So, the weather was merely an inconvenience and not a problem. After all, most of us trekkers have to deal with such low temperatures only for a day or two. In Roswell, the temperature soon peaked at 61F!

Rule #3: When travelling in the winter, spring or fall, take along a couple of gallon jugs of drinking water and keep this inside and warm. We use this when we travel with winterized tanks. In other words, this might be the only drinking water available. Of course, you can use the toilet if you flush with pink anti-freeze, and we do that rather than getting out of the RV in the night to use the nearby toilet facilities, if there are any.

Rule #4: Take a supply of potable water system antifreeze and be aware of how to winterize your RV. We had done the above and so the re-application of anti freeze on a recent trek was simply an inconvenience.  As the temperature plummeted we dumped the gray and black water tanks, emptied the outside fresh water tank and simply added about a gallon of "pink" antifreeze to the outside fresh water tank. We then pumped it through the system and added some to the P-traps and toilet. It took about 30 minutes. This would have been a major problem had we not packed two gallons of anti-freeze. That is one of the reasons I consider our 210P to be the personal minimum space for two. We had the room for that anti-freeze, and all of our other gear and firewood and BBQ, too!

Rule #5: Know your RV. We travel with a copy of all of the manuals for our RV, and that includes the furnace, macerator and convection oven. I made it a point to check the model numbers of everything by looking at the plates on the equipment. Do you know which specific model battery separator your RV has? Or toilet? Or inverter? When things go wrong, that information is invaluable when you call on your cellphone for help.

Rule #6: Make certain your propane tanks are full before any trek.  We had done that. So when the outside temperatures dropped, we used the portable electric heater but also set the propane furnace at 65F, in the event interior temperatures fell or the electric heater could not keep up.  We were toasty throughout the night. Why have a home and live as if it is a cave?

Rule #7: RVs are metal cans and are not sealed to be airtight. (Mine is fiberglass shell and steel body). Most have single pane windows. In other words, if the insulation is R4.5 you are doing well; but those windows have an R value of about 0.91 (useless insulating value). In layman's terms, you will probably experience drafts and cold zones at night.

To be comfortable at lower temperatures we decided we needed to do a few things to improve the vehicle comfort.  Some of these are useful in higher temperatures, too.

Rule #8: Insulate your windows. We use aluminized bubble wrap insulation on our windows (Reflectix) and that makes quite a difference in both low and high temperature extremes. I cut the pieces to fit and roll them up and store them under the electric sofa bed when not in use.  I always put the window insulation in place in the coach area at night if the outside temperature is to stray very far from a mild 70F.  If it is mild, I may skip the front (driving) area. Single pane windows, with Reflextix have an R-value of about 2.0, which is about double the insulating properties of glass.

Tip: for extra comfort in the sleeping area use two layers of insulation on the rear windows.

Rule #9: Sleep warm and comfortable. If you have a good, restful sleep you will have a better day. We've used a variety of sleep aids including polartec fleece blankets and wool, but an electric blanket is probably the best when temperatures fall.  When I sleep at home I sleep in a bed with blankets. I don't sleep in a sleeping bag. That's what I expect when I sleep in my RV; a bed with blankets and that's what we do. We have a king sized bed in our 210P and we enjoy it. The sleeping bag I store with my tent.

We experimented with a small heating pad and liked it. So we now have a queen sized electric blanket. We set it at the lowest setting. With good blankets that is sufficient. The electric blanket is really helpful for anyone with arthritis.

Our electric blanket has independent dual controls with 10 heat settings each. It's a queen size and at the lowest setting uses 110watts per side. That's per my Kill-a-Watt P3.

We've found the lowest setting on the blanket "L" to be more than sufficient. If you want a boost, select the "preheat" feature to get your nest nice and toasty before entering for the sleep.

With an electric blanket I suspect we'll probably use less electrical power. I am also experimenting with a 12V fan to get better airflow in the sleeping area.

Rule #10: If you want that gasoline generator to start, keep it maintained and use a gasoline additive. I do run ours monthly and I add SeaFoam motor treatment additive regularly so as to be assured that the carburetor of the generator has additive in it. When we are travelling from point A to point B I see no reason to add an additive with each tank of gas. So I carry a 1 liter bottle in an outside compartment and add it to the last tank of gas for our trek. We begin the trek with additive in the tank and we end it with additive in the tank. I run the generator at the end of the trek to assure that there is additive in the carburetor. To save money, I purchase the additive in a gallon container at an auto parts store and transfer it to the smaller 1 liter container. I have used less than a gallon in 12 months.

This tip could also be entitled "Keep your RV maintained." If I want the generator and other systems to perform on demand that is a must. This is also why I am committed to replacing the AGM batteries.

Rule #11: Smaller is better, in my opinion. Many won't drive a larger RV through winter storms; I've never done that, but I have driven this RT in snow and ice. I've also driven a truck in bad weather and so I have an appreciation of the concerns of the Class A driver. It wasn't fun  but there was a deadline and I did need to be at the destination on time. For RV trekkers, that is not a paramount consideration and one can park the RV and ride out the winter storm. We did that for part of our first winter trek. We drove as long as possible to get beyond most of the storm, found a nice overnight spot and fired up the generator and propane heater. We were able to continue on our way the next morning and I have found that a rear drive "van" is reasonable and comfortable in many weather conditions. I also prefer the small, side entry door for entering the living space. Really wonderful for quick entry or exit in winter. We did rent a Sprinter and that large sliding door is enjoyable for admitting the outdoors when the sun is shining and it is mild. It sucks in rain, sleet, snow and when it is really, really cold outdoors.

It's useful to keep in mind that each time one opens that living space door, one lets all the heat out and in comes the cold, rain and snow.  The front passenger seat has been rotated when we are stationary and climbing over front seats with boots, etc. is simply not a good idea. That's my experience. It hit home when we rented a Sprinter. Yes, during those wonderful, mild and bug-free days we enjoyed that sliding door. But overall, we really prefer the smaller, easy open side entry door of the Chevy van.

Sprinter and the Outdoors

RT210P - Smaller side entry

There are other things one can do, and I could make an endless list. However, there are things we do that really make a difference and the above I consider most important. 

Comment: Our first winter trek was a spur of the moment decision. We quickly packed clothes, canned goods, boots, cold weather gear, kitchen stuff, tools, antifreeze, water, a VOM and duct tape, Goop, scotch tape, a white and black paint marker, 12V battery charger and so on. We really had enough stuff and the only thing we needed to purchase besides gasoline was a roll of teflon tape for the hot water heater anode. But, we have learned more about comfort and what it takes to be both confident and comfortable on our treks. Perhaps I'm a Murphy's Law buff. But in my business that is what it takes. I prefer to have more data on how the camper van systems are doing, and I also like to pack for breakdowns. So I've begun to improve the instrumentation on the internal systems of the camper van. The RT 210P is pretty good, but for example, adding internal, external and refrigerator temperature sensors is an aid. Ditto for better power monitoring (AC volts, current draw, frequency) and that includes a desire for better condition monitoring of the coach batteries. I haven't really spent much money doing this (less than 1% additional as compared to the original purchase price), but it really builds one's confidence when camping in very cold weather. My spouse who is somewhat skeptical now enjoys our treks with significantly less trepidation than she did that first one. Alaska, here we come!

Are Lithium RV Coach Batteries Expensive?

Here's a bottom line for a small RV system, using off the shelf lithium battery components. I'm editing this post to add the following which I think is a very important consideration:

AGM batteries 220Ah = 110Ah useable,
Lithium (LiFePO4) 200Ah = 160Ah useable,

In other words, a similarly rated lithium battery system will probably deliver about 45% more power than a similarly rated AGM battery system, and it will probably do so for at least 6-7 years. Now do I have your attention?

What I am planning is not a "build it in your basement" system comprised of battery packs assembled at home from hundreds of batteries. There are some serious considerations when using lithium batteries, which can be safe and environmentally superior to lead acid batteries. Those batteries do require monitoring and controls so that a cell failure can be managed. My concept system which will probably be built is comprised of pre-assembled batteries packs and off the shelf controllers and solar panels. This system is similar in design to current AGM coach battery systems:

Battery watts: 1200 (or 2400) (1.2-2.6 kWhr, replace 2-6V 220Ah AGM batteries)
Solar Panel = 140 Watts
Cycles: 2000 to 3000 at 70-80% discharge (DoD). Up to 5000 cycles possible. (See notes).
Self discharge = less than 3% per month.
Battery weight = 25 to 33 lbs.
Battery storage temperature limits = -20 to 114F
Battery operational temperature limits = 32 to 114F (some batteries are rated 5F to 115F).
Includes MPTT Solar Controller and 140 watt solar panel.
Includes 120V charger for lithium batteries.
Cost of entire system components: $1,690 - $2,600

Why the cost differences above? There are different technologies available. The most reliable are the most expensive. I think the lower number is realistic. After all, I won't be sailing my RV around Cape Horn. Note: Read the notes at the conclusion of this post for some important info that impact the specifications above.

Can I Get More Power?
The above can be "scaled up" with more batteries, larger solar panels, etc.  A 2400 watt (whr) system could cost about $3,000. The batteries would weigh about 60-65 lbs, which is about half of a similar AGM battery. The costs are for components, but excludes installation and tax.

A 4800 watt system could cost about $5,600.  As you can see, at the higher wattage the cost is approaching about $1 per watt. However, it is possible to get batteries for as low as $0.55 per watt.

Quick Comparison - AGM Limitations versus Lithium
It's useful to keep in mind that the list price of an additional 2400 watts of AGM batteries in a Roadtrek 210P is currently $871. The battery cost difference is why lithium is not currently standard. In recent years there have been some real price drops in lithium and today, 2400 watts of AGM batteries cost about $500-600 while similar lithium batteries begin at about $1,800.

However, AGM batteries are temperamental. They have longer charge times, can and do sulfate, weigh twice what lithium batteries do. AGM batteries perform longest with a 50% discharge (50% DoD, or Depth of Discharge). In other words, a lithium battery with an 80% DoD limit can provide 30% more power each and every day as compared to an AGM battery. Such a lithium battery is designed for at least 2000 cycles, which is about 7 times the life of an AGM battery. Achieving 5000 cycles would result in a system which could have a life measured in decades.

Of course, any RV manufacturer's pricing includes mounting and wiring systems as well as installation labor, etc. I am convinced I could install an entire system, including improved solar and MPTT charging system with at least 2400 watts (whr) of lithium power for a cost of about $3,000. If I want to get wild, I could go for 4800 watts at about $6,000.  The 2400 watt system would be almost a "drop in" solution. 3600 or more watts would require a closer look at the available battery space.

Other Battery Considerations
One more thing to consider is cycles. That's the number of times a battery can be charged and discharged. A Deep Cycle AGM battery, if discharged to not less than 60% the cycle life will be 300 plus cycles. (That's per reputable battery sources). An AGM battery might achieve 500 cycles. A lithium battery is good for 2000 to 3000 cycles at 80% DoD and ideal temperatures (see the notes). In other words, a lithium battery system is rated for a lifespan 6 to  10 times longer than that of an AGM battery system.  That is one of the reasons manufacturers are beginning to look seriously at replacing AGM battery systems with lithium battery systems.

What's the Limit?
Most costly component is the batteries. To get to 20,000 watts as Roadtrek is experimenting could require about $10,000-$12,000 in batteries (at wholesale). I would guess those batteries weigh about 500 lbs. However, to put this into perspective a Roadtrek 210P comes "stock" with two AGM batteries rated a total of 2400 watts. 4800 watts with AGM batteries weighs in at about 280 lbs.

What does 20,000 watts of AGM batteries weigh?
I'd guess that 20kW (kWh) of AGM batteries would weigh in at about 1,200 lbs plus the weight of the system to contain them. Similar capacity lithium batteries would weigh about 500 lbs. However, there are differing lithium battery technologies available, and that influences both volume taken by the batteries and weight. (See note 10).

Why would I do this? 
Well, I think I'll be replacing my AGM batteries next year, less than 36 months after vehicle purchase. Replacement with similar batteries will cost me about $600. In other words, the battery cost has been about $300 per year. Add to that the following possibilities achievable with an upgrade:

• zero maintenance with solar (I do have solar on the AGM batteries)
• no lead
• 10 year life (okay, let's assume 6 years at 75% real, available power).
• 80% depth of discharge
• A real 1920 watt-hour available rather than pretend 2400 which is at best 1200.
• I'd like to get more electrical power when off the grid than I do currently, and I'd like to achieve this without running the engine, or starting the generator. I'd also like to have more power available for cooking when off the grid and conserve propane. I have no intention of living on solar power.  The existing system is rated about 1.3kWh and I think I can double that with the lithium batteries. 
• No need to charge below freezing during vehicle storage. It's my understanding that lithium (LiFePO4) batteries should not be charged if they are below freezing. However, they can be stored for long periods under freezing conditions and can discharge okay in cold weather. (Note 11).

Notes:

1.  I have the advantage of being able to prototype and test such systems. I think a "drop-in" upgrade package for RVs would be useful.
2. I'm currently most interested in LiFePO4/LiFeMnPO4 battery technology. I want batteries which are safe.
3. Costs are determined by battery technology.
4. Battery prices are all over the map. Lowest cost is about $0.55 per watt (whr).
5. Battery life for AGM lead-acid and lithium (LiFePO4) batteries are determined under somewhat ideal conditions. Those conditions include ideal DoD as well as ideal ambient temperatures. Battery life is reduced under higher temperatures. What's ideal? Depending upon the battery, 74-77F is ideal.
6. In the real world some RVers are attempting to live off solar systems with lots of solar panels and large battery systems. This requires sunshine.  Unfortunately, many such sunny areas also get higher ambient temperatures and that's not good for batteries. Over in Tucson they talk about five annual seasons, of which one is named "fire." Elevated temperatures reduce battery life. So what's reasonable? I'm going to assume a 25% reduction in battery capacity within 5 years. However, for a  lithium (LiFePO4) battery that would be far superior to my AGM batteries.
7. A lot of what we know, and what we are doing, is based upon lead acid battery technology. For example, with AGM batteries it is preferred to keep them fully charged. So this approach was also applied to lithium batteries. However, there is now a concern that maintaining lithium batteries at full charge may actually reduce their usable life. In other words, there may be a trade-off and that has fueled some argument about what is the best way to maintain lithium batteries while achieving the longest possible life.
8. I am concerned about the above. A lot of what we currently know is based upon old lead-acid theory and requires years to validate in the "real world." When one is spending $thousands on batteries, that should be a concern. Roadtrek currently has a prototype with 20kW (kwhr?) of lithium batteries. Will they get it right?
9. Why do this? I'll post on that later, but I've provided a brief explanation in the text of this post.
10. You may wonder about that 20kW number. That's what a Roadtrek blog has stated a prototype lithium system has. I assume they meant a capacity of 20kWh (20 kilowatt hours). Not beyond the realm of possibility. I've seen a similar battery pack and it measures about 25 inches x 24 inches x 15 inches and weighs in at about 425 lbs.
11. It's my understanding that it's okay to discharge these batteries if the temperature is below freezing and they can be stored for long periods below freezing. However, they should not be charged if the temperature is below freezing. This will require some additional research on my part. 

Oops, I am so used to working in higher power systems I typed "kW" in several places when I should have typed "W." I have corrected this and now indicate "watts" where that is so. I also omitted the 120V charger for the lithium batteries on my list. It was included in the costs. It may not be clear from this post, but I could achieve an increase in available kW with the lithium batteries. My current 6V batteries are rated 220Ah under "ideal conditions."

AGM Battery Alternatives

It's again that time of year when attention goes toward the coach batteries in the RV. When the RV is in frequent use, this is never an issue. Running the engine will charge those batteries, as will plugging into shore power.

However, in winter, some of us put our RV into storage. Those AGM coach batteries then self-discharge. Sulfation may occur and if the batteries are sufficiently discharged they may freeze and undergo permanent damage. In winter, our attention turns to the coach batteries. When spring arrives some of us may be unhappy to find that our batteries have only 75-85% of rated capacity, or less.

Is There a Better Way?
In my case, I installed a 50 watt solar panel and charging system to help those AGM batteries. I also installed a smaller solar panel to offset parasitic drain for the engine battery. Both of these have seemed to help. I went to the storage facility for my RT and the coach battery monitor indicated my coach batteries were in "fair" condition. That has been typical; I suspect my RV which was purchased one year after manufacture had damaged AGM batteries. My current interest is in getting the maximum benefit from whatever coach battery system I have.

On my most recent RV inspection the engine started fine and I charged the coach batteries for a half-hour. Not a lot, but intended to augment the solar charging system.

But is there really a better way? I think lithium batteries are the way to go. I've begun exploring this.

1. Smaller lithium battery systems have been proven in sailboats.
2. Faster recharge times. 
3. Lithium batteries have half the weight of the AGM batteries on a weight versus output basis; that's another 70 lbs. of gear, or improved fuel economy, in my case. Or more battery capacity at the same weight!
4. Lithium batteries, while more costly initially do have a higher number of charge-discharge cycles and can tolerate deeper discharges. In simple terms, they will last far longer than the AGM batteries. 
5. There is some evidence that lithium batteries cost less over the life of the battery than do AGM batteries. For anyone who intends to use a RV for 10 years or so, this is significant. 
6. Lithium batteries don't freeze at low temperatures and have the winter problems of AGM lead-acid/water batteries. In other words, fewer winter maintenance issues. Roadtrek states in their 2014 210P manual "AGM Battery Warranty....... is voided if AGM batteries are tampered with, topped off with distilled water or allowed to sulfate or freeze due to lack of charge."
7. Lithium batteries have lower self-discharge rates. In other words, they can be stored for extended periods at full charge and don't self deplete. 
8. Lithium batteries can tolerate deeper discharge than can AGM batteries.
9. AGM batteries have high ambient temperature restrictions.  AGM batteries are designed for an average annual temperature of 77F (25C). If the average annual temperature is 95F (35C) then the battery life will be reduced by about 50 percent. 

Improving Solar Response
I've also been researching improved solar panels and I've decided it would be pointless to put them on an AGM battery system.  Improved solar panels would benefit with an improved electrical storage system. In other words, the system is limited by the weakest link in the chain.

I'll continue my research and will post the upgrades as I make them.

Why Do Manufacturers Use AGM Coach Batteries?
That's a question you might ask. The reasons are straightforward.

1. AGM technology is well established and existing system designs are in place.
2. Alternative battery technologies, such as lithium, are at a higher initial cost. This increases the purchase price of the RV.
3. New designs will require engineering manhours which is an additional cost to the RV manufacturer.
4. Other technologies are new and are not well understood. In other words, while technically superior, some technologies have not yet been widely offered because the sales, marketing, management and engineering departments at RV manufacturers have not yet come to grips with the benefits.
5. It's a competitive world. Most users (RV buyers) compare total cost to overall performance. It's only after purchase that the limitations become apparent.
6. Leadership entails risks. However, most western companies are risk-averse. My company recognized this. We were leaders in our field and as president I would remind our employees that "There is the leading edge, and then there is the bleeding edge." I can say that we did find ourselves from time to time on the "bleeding edge." Good engineering, attention to detail and serious prototyping kept us and our clients from going over the edge. I would say that lithium batteries, which are well proven in smaller systems such as sail boats are not at all like what I was facing with hardware and software which didn't perform as expected. This isn't 2008, nor was the microprocessor invented only four years ago. This is 2015 and there are a lot of Tesla motor vehicle on the road, and lithium batteries are not uncommon on sailing vessels. Lithium batteries are entering the mainstream.