Frequently asked questions…
Lithium battery technology is relatively new when compared to lead acid batteries which have been around for 100 years or so. Despite lithium batteries being used in phones and laptops for decades there is a lot of misinformation in the public domain around lithium batteries in particular surrounding their safety. So, we have compiled a comprehensive FAQ database which will hopefully answer your most common questions or concerns.
Battery Management Systems
Our Battery Management System (BMS) is made up of a printed circuit board which monitors and manages the 4x 3.2V lithium cells to ensure they are charged and discharged together and at the same rate. It also provides protective features to prevent over charge and over discharge of the cells, keeping the battery within a safe operating envelope. Our innovative BMS is also designed to be able to draw up to 250A on the load side and charge at up to 100A.
A Battery Management System (BMS) is a key part of a lithium battery. Unlike lead-acid batteries which do not require a BMS, lithium batteries do. A BMS primarily is a circuit board which manages, monitors, controls and protects the lithium cells from being over charged or over discharged, which can lead to permanent damage or in the worst case lead to fire. It also needs to be able to disconnect your battery before the cells go outside of their safe operating limits. Therefore it is vital that your investment in a lithium battery is not compromised by using an inferior BMS. That is why we have opted to design, engineer and manufacture our very own BMS right here in Brisbane, Australia – so that we can control its functionality, quality and reliability.
The simple answer is no. With a lead acid battery voltage begins to drop as soon as a load is applied and so the drop in voltage over time can be used to estimate state of charge. Because lithium batteries have a very flat volt curve, voltage cannot be used to determine the battery’s state of charge. Instead we have to count amps in and amp out of the battery to calculate the state of charge. This requires a software algorithm within the BMS to perform and display on the screen as a 0-100% readout.
Yes. All of our lithium batteries are supplied with a remote display LCD screen control panel (connected via cable to our battery) which gives you access to vital information like SOC (state of charge), hours remaining at current usage rate, voltage, temperature etc.
In most cases yes, but it is best to contact us first to confirm. We will let you know if your charger, whether it be solar, DC from the alternator or AC mains charger is compatible with our lithium batteries.
Our 100Ah lithium batteries can be charged in one hour with the correct chargers which is 2.5 times faster than lead acid batteries. You can charge our lithium batteries at 100A total, which could be a combination of solar, DC and AC chargers.
Our lithium batteries deliver at least 6 times more usable amp hours over their lifetime compared to lead acid batteries. This reduces the cost of replacement, installation and inconvenience every 3 years, saving you money in the long run. You have to look at the total life cycle of the battery and not just the upfront cost.
There are numerous advantages that lithium batteries have over lead acid batteries with respect to recreational vehicles such as caravans, motorhomes and camper trailers. These can be summarised as:
- Weight – lithium batteries are half the weight as lead acid equivalents which is important in an RV. A 100Ah lead acid battery weighs around 30kg, whereas our 100Ah lithium battery is 15kg.
- Depth of discharge (DOD) – lithium batteries can be safely discharged to 80% DOD compared to typically 50% DOD for lead acid batteries. This means for a 100Ah battery you have 80Ah available to use with a lithium battery and only 50Ah with a lead acid.
- Constant voltage – lithium batteries discharge at more or less a constant voltage until they reach around 80% DOD, after which the voltage begins to drop off. Compare this to a lead acid battery where voltage begins to drop as soon as power is drawn. This means that with a lithium battery, low voltage disconnects to protect appliances are not activated before the battery is empty like they are with a lead acid battery.
- Cycles – lithium batteries last a lot longer than lead acid batteries, in that you can cycle them more times before they need to be replaced. Our lithium batteries are rated at 2,000 cycles times at 80% DOD compared to a lead acid battery at 500 cycles.
- Power output – our 100Ah lithium batteries can discharge at up to 250A which is made possible by our BMS. Many other 100Ah lithium batteries used in RV’s limit you to 100A. 100Ah AGM batteries struggle to provide even 100A. Being able to discharge at 250A allows the RV owner to run high power appliances such as microwaves, kettles, coffee machines etc.
Yes, some do and have done in the past. But we need to understand that there are many different lithium ‘chemistries’ on the market today, some are more volatile than others. We use lithium iron phosphate, a particular type of lithium ion chemistry that is considered the most stable and not prone to ‘thermal runaway’ (which is a fancy name for fire). Our cells have even undergone puncture testing with a nail – no fire or explosion resulted. This also highlights the safety-critical importance of a Battery Management System (BMS) which has the important job of preventing the cells from going outside the safe limits in the first place. In fact I would say that it is usually the fault of a dodgy or ineffective BMS that causes thermal events. Therefore the cells that we use, in conjunction with our BMS, provides for a very safe and reliable battery.