Lithium-Ion Phosphate Motorhome batteries (A.K.A. Li-Ion) have been around for some time now, the price has begun to drop following mass production from companies like Tesla. The main difference I have seen is that the quality is improving, you can now achieve a 50% discharge up to 8000 times or an 80% discharge up to 5000 times from a Lithium-Ion battery!

If you are serious about going off-grid with your motorhome, horse box or expedition vehicle then Li-Ion is by far the best option. The performance difference between a Li-Ion battery and a traditional ‘Lead-Acid’ battery is so great that it is an easy decision to upgrade.

Below I have listed the main benefits of Lithium batteries that can be used in a motorhome, horse box or expedition vehicle:

• The voltage remains constant until the battery is almost 100% discharged

• All the batteries we supply can accept a charge equalling, and in some cases exceeding its capacity. This means that if you have a 100ah battery you can charge it at 100 amps, even from an alternator supply!

• In the case of a 100ah Li-ion Lithium battery you can draw 1 amp for 100 hours or 100 amps for 1 hour and everything in-between.

• You can safely discharge a Li-ion Lithium battery to 100%.

• A Li-ion Lithium battery can be discharged up to 80% 5000 times. With a flooded, ‘Lead-Acid’ celled battery this can be as low as a few hundred discharges.

• Li-ion Lithium motorhome batteries are 60% lighter than the equivalent lead-acid battery.

• Li-ion Lithium batteries have a very low rate of self-discharge. This means they can be left for months without requiring a charge.

• Li-ion Lithium motorhome batteries are completely maintenance free.

• Li-ion Lithium batteries can be installed in any orientation.

• Li-ion Lithium motorhome batteries can replace a lead acid battery with minimal modifications.

For those who are interested I will now elaborate on each of the points above.

• The voltage remains constant until the battery is almost 100% discharged. With a lead-acid battery, the more you discharge the battery the lower the voltage will go. You can normally only discharge a lead-acid battery to about 60% of its amp hour capacity, after this the voltage drops so low it will no longer operate high demand 12 volt draws such as an inverter or possibly a levelling system. Li-ion batteries will retain a voltage of approximately 12.8 volts for at least 95% of the capacity.

• All the batteries we supply can accept a charge equalling, and in some cases exceeding its capacity. This means that if you have a 100ah battery you can charge it at 100 amps, even from an alternator supply! You can normally only charge a lead-acid battery safely using a charger rated at 10% of the capacity of the battery. This means that if you have a 100ah battery you can only use a 10 amp charger, and it will take 10 hours to charge your battery. If you have a 100ah Li-ion lithium motorhome battery you can use a 100 amp charger, this means that you can charge it in 1 hour! In some cases using the correct Battery Monitoring Systems (A.K.A. BMS) you can charge a Li-ion battery up to 3 times its capacity; this would mean you could potentially fully charge a 100ah battery in 20 minutes.

• In the case of a 100ah Li-ion Lithium motorhome battery you can draw 1 amp for 100 hours or 100 amps for 1 hour and everything in-between. You only have about 60% usable draw down on a lead-acid battery, you may think you have purchased a 100 ah battery but you can only use 60% of the power. This is not the case with Li-ion, the full capacity of the battery is usable. In fact using a Transporter Energy Battery you can draw 200 amps for 30 seconds and it will allow up to 300 amps for ½ a second.

• You can safely discharge a Li-ion Lithium motorhome battery to 100%. As I have mentioned above you can use the full capacity of the battery. There is different quality of Li-ion batteries, some you can only charge at 25 amps some can charge at 50 amps, these lower quality batteries can only be discharged to 95%. Be sure to speak to us before you upgrade your battery!

• A Li-ion Lithium battery can be discharged up to 80% 5000 times. With a flooded cell lead acid battery this can be as low as a few hundred discharges. A good quality Li-ion battery will last far longer than a lead-acid battery, this can actually make them a far cheaper option over the life of the battery than a lead-acid battery.

• Li-ion Lithium motorhome batteries have a very low rate of self-discharge. This means they can be left for months without requiring a charge. If you leave a lead acid battery unattended for a period of time it will discharge itself. A Li-ion battery will not, in fact some Li-ion batteries can be left for up to a year with minimal discharge.

• Li-ion Lithium motorhome batteries are completely maintenance free. Once you have installed a Li-ion battery you can almost forget about it. If you are planning to leave your vehicle for a long period of time, either parked inside, or if you don’t have a sufficient solar system it may be worth disconnecting your battery. This will increase the life of the battery as they are not keen on being left in a discharged state for a long period.

• Li-ion Lithium motorhome batteries can be installed in any orientation. Flooded Lead-Acid celled batteries can only be mounted in an upright position, some AMG and Gel batteries can be laid on their side. If you have limited space, putting a battery in a different orientation can make it possible to install it in an area that you would not normally be able to.

• Approximately 60% lighter than lead-acid batteries of the equivalent amp hour rating. The Transporter Energy Battery only weighs 13.1Kg, to obtain the same amount of usable power from a lead acid battery you would need almost 200ah. A 200Ah flooded cell battery weights 50kg, a decent AMG will be 60kg, and pure lead AMG is 78kg. If you want to increase your payload moving to Li-ion is an excellent idea.

• You can replace a lead acid battery with minimal modifications. Historically if you wanted to install a Li-ion battery into you motorhome, you needed to replace the battery charger and the solar regulator to products that can support Li-ion. This is no longer the case, the Transporter Energy battery can be charged from the battery charger installed by your motorhome manufacturer. It is possible to simply remove your existing battery and install the Li-ion, however I personally think by doing this you are not exploiting all the benefits. Replacing your mains charger can sometimes be problematic as these are normally integrated into the vehicle. I would normally recommend upgrading your split charge system, most motorhomes have a surplus of 100 amps available from the alternator, so why not use it? We use Victron Cyrix relays, these allow all the available power to be drawn into your new Li-Ion leisure battery.

Frequently asked questions about installing Li-Ion Batteries into a motorhome, horse box, boat or expedition vehicle.

Q) Are Li-Ion Lithium motorhome Batteries safe?
A) As long as Li-ion Ion batteries are installed correctly they are safe. Many high end motorhome manufactures are now installing Li-ion batteries as standard. At RV Installations we have experience of installing Li-ion batteries to many different makes and types of vehicle. You can be sure that if we install a Li-ion battery into your vehicle you will have no safety concerns. Where and how we install the battery will depend on the intended use. If you are planning an expedition to the Arctic Circle we will look at ways of keeping the battery warm, if you’re planning to cross deserts we will look at ways of keeping the battery cool. If you are planning to remain in the UK and Europe then it is likely that it can safely be installed with no battery box modifications. A Transporter Energy Battery can be discharged between -20 and +71 degrees Celsius, it can be charged between -4 and +57 degrees Celsius.

Q) How do I know which battery to install?
A) There are now many different manufacturers of LiFePO4 batteries. Some are better than others. I have mentioned Transporter Energy batteries, these batteries can be paralleled to increase the battery bank capacity or can be connected in series to increase the voltage. We can also install Victron 24v Li-Ion batteries and in certain scenarios 48v Li-Ion batteries. Your battery choice will depend on the intended usage. If you need to run a 1kw inverter then you will be safe with a 100ah battery, if you have a 2kw inverter you will need 200ah and so on. If you need to run critical systems where system failure is not an option, such as medical equipment, then the design of the system will be different to allow redundancy in the system. If you have a 12v system then you would require a minimum of two 12v batteries, if you have a 24v system you would require a minimum of four 12v batteries or two 24v batteries. These batteries would be connected in such a way as to allow a single battery failure without compromising the operation of the equipment. At RV Installations we design a bespoke system for every customer to ensure the system we install is correct for their intended use.

Q) How do I know what size battery I need?
A) Every time we talk to a customers about installing a Li-Ion battery we ask the same question, “What do you want to run and for how long?” We will then calculate the daily power usage and base a system around that usage, with a possible future expansion in mind.

If you require any additional information or would like to book your vehicle in for us to carry out an upgrade, please contact us.