City life makes us feel boring, and it’s a wonderful thing to travel in an RV during the holidays. If you want to travel far, your RV may need to be equipped with a solar power system, batteries to store electricity, inverters, etc. So how should you choose between lithium batteries and lead batteries?
More capacity with a lithium battery in the RV
As a result of the fact that a lithium battery is lighter and smaller than a lead battery with the same capacity, you can of course turn the whole thing around and instead enjoy more capacity with the same space and weight. Space is often still saved even after a capacity increase.
With our upcoming switch from AGM to lithium batteries, we will triple our usable capacity while taking up less space.
Lithium battery life
The lifespan of a lithium battery in a RV can be quite enormous.
This starts with the fact that correct charging is easier and less complicated, and that it is not so easy to affect the service life through incorrect charging and deep discharge.
But deep cycle battery also have a lot of cycle stability.
Example:
Suppose you need the entire capacity of a 100Ah lithium battery every day. That means you would need one cycle daily. If you were on the road all year round (i.e. 365 days), then you would get by with your lithium battery for 3000/365 = 8.22 years.
However, the vast majority of travelers are not likely to be on the road all year round. Instead, if we assume 6 weeks of vacation = 42 days and add a few more weekends to a total of 100 travel days per year, then we would be at 3000/100 = 30 years of life. Huge, isn’t it?
It must not be forgotten: The specification refers to 90% DoD. If you need less power, the service life is also extended. You can also actively control this. Do you know that you need 100Ah daily, then you could just choose a battery that is twice as big. And in one fell swoop you would only have a typical DoD of 50% which would increase lifespan. Whereby: A battery that lasts longer than 30 years would probably be replaced because of the expected technological progress.
The long service life and the high, usable capacity also put the price of a deep cycle AGM battery in a RV into perspective.
Example:
- A Bosch AGM battery with 95Ah currently costs around $200.
Only about 50% of the 95Ah of an AGM battery should be used, i.e. 42.5Ah.
- A Renogy RV lithium battery with a similar capacity of 100Ah costs $1000.
At first that sounds like five times the price of the lithium battery. But with the Renogy, over 90% of the capacity can be used. In the example, it corresponds to two AGM batteries.
Now the price of the lithium battery, adjusted for the usable capacity, is still more than double.
But now the cycle stability comes into play. Here the manufacturer’s information varies greatly – if you can find any at all (with ordinary batteries).
- With AGM batteries one speaks of up to 1000 cycles.
- However, LiFePo4 batteries are advertised as having over 5000 cycles.
If the lithium battery in the RV actually lasts five times as many cycles, then the lithium battery will overtake the AGM battery in terms of price-performance.
Of course, this is based on some assumptions, and if these are not 100% correct, the calculation can also deviate in one direction or the other. But the bottom line is: RV batteries are a considerable investment, but over time they are not more expensive than ordinary batteries. And you still enjoy all the other advantages.
Disadvantages of the lithium battery in the RV
There is no light without a shadow – even a lithium battery has some disadvantages. All in all, the list of disadvantages is quite short and clear. fall under
- The price of a lithium battery
- The necessary charging technology and
- Using the lithium battery in cold weather as well
- Possibly lack of long-term experience
Lithium batteries in motor homes have their price
The most obvious disadvantage of lithium batteries in the RV is the price. Lifepo batteries are not cheap. While price must be weighed against benefit and service life, a lithium battery is undoubtedly a significant investment.
Charging technology for lithium batteries in RVs
In addition, technical changes in the area of phosphate charge may be necessary for the installation of a lithium battery in the RV. But some plug & play solutions are also offered, where the manufacturers explicitly advertise that the charging technology can be left as it is.
However, these advertising promises do not say whether this also ensures the optimal service life of the lithium battery. So keep that in mind.
Limited long-term experience with lithium batteries in RVs
In addition, there is still a lack of real long-term experience, since at least the camping products have not been on the market long enough to have reached their promised service life.
Charge lithium batteries in the cold
The fact that lithium batteries do not like to be charged in the cold is often cited as a problem.
In fact, lithium batteries can be charged within a certain temperature range, minus degrees are usually taboo. It is also more difficult to draw current from a certain, low temperature.
The exact temperature thresholds can be found in the data sheets for the respective battery. From our point of view, the problem in the RV battery is usually not as relevant as it is claimed.
Because when you are traveling in a RV, you will hardly let the interior cool down to minus degrees, but heat it up. And then the lithium battery in the RV works perfectly. The problem really only exists when the battery itself cools down to 0 degrees or less. Especially when the battery is installed in the living room, this doesn’t actually happen during operation.
However, it is of course true that driving off in winter after a longer standstill can be problematic. It may then not be possible to start up the RV heating system, as this would require electricity.
Monitoring screen for DC-DC MPPT battery charger series. And when you drove off, the alternator would charge the battery right away, even though the battery might not have warmed up yet.
However, this can be prevented by the correct functioning of the BMS (battery management system), and after some driving time the cab heater should be able to warm up the battery again (depending on the installation location).
There are now some manufacturers who come up with special lithium batteries for RVs, which are also suitable for low temperatures. You should decide for yourself whether you actually need it. This can be relevant if you install the batteries in expedition vehicles, for example, in an outside storage box that is not heated. You may need to use some mounting brackets when installing. It simply uses heating elements to keep the battery warm.
Who needs a lithium battery in the camper?
For whom is a lithium battery in the camper now suitable?
Well, obviously for those who need the benefits.
- Travelers who want to operate a self-sufficient RV without infrastructure have the advantage of greater capacity with lower weight/space requirements with lithium.
- If you use a DIY solar power system in the RV, you will be able to use the energy of the solar system better with a lithium battery, because lithium batteries can be charged better.
- For those campers who want to do without a solar system or who cannot operate one sensibly because of the weather conditions, a fast-charging lithium battery in connection with a charging booster can represent a self-sufficient energy concept on its own. Because it allows the lithium battery in the RV to be charged quickly while driving, which is then sufficient until the next day. But users of solar systems on the camper can also cheat on bad weather days.
- Motorhomes with weight problems can save a lot of weight with lithium batteries. Upgrading from 2xAGM to 1xLithium at the same capacity can save 60kg.
- Campers who want to operate 230V devices on the solar inverter get a more suitable power supply with a lithium battery.
But not everyone needs a lithium battery in their camper. Anyone who would not use the advantages anyway can save a lot of money with ordinary batteries – at least at first glance, because how calculated is this put into perspective over time.