There are still some people nowadays that use lead acid batteries for off grid use, but more and more of them are moving to a newer type of battery. There have been many things being said as to the usefulness of lithium ion batteries for such applications, but let us set the record straight.
・Do lithium ion batteries for home off grid use really work that well?
・Are they really objectively better than lead acid batteries?
Well, the short answer is yes, and lithium ion batteries remain one of the best choices for off grid use today, for several reasons.
In this articles, we are going to explore those reasons and we will see how lithium ion really fares against lead acid batteries (or any other type of battery, for that matter), when it comes to off -grid applications.
We cannot blame people for sticking to lead acid batteries for such a long time. This battery type is trusted, as they have been tried and tested for many years to be part of energy systems.
Meanwhile, the integration of lithium ion batteries in such systems may be as complicated as it is perceived to be. However, we can tell you outright that transitioning to lithium ion is very much worth it.
Such is the belief that lithium ion batteries is the future, that in a few years, lead acid will be obsolete and will be completely replaced by this newer, better battery type.
More and more companies even get a sense of this, with many of them trying to propagate a cost-effective way to spread lithium ion batteries in energy systems, whenever they can.
Going for as low as US$400 per kilowatt-hour, companies like Lithionics, LG Chemicals, Sonnen, Simpliphi Power, and even Tesla are promoting this new type of battery.
Add to this the natural resilience, the higher density, and the improved battery life of lithium ion and w already got a clear winner. Still, lead acid batteries have been around for about a couple of centuries, and it has been on the top of the battery game for so long that some people think it is unnecessary to replace them.
Lead acid batteries are so commonplace; it will not be surprising to find them in a variety of quality, from the very best to the very poor. Companies like MK/Deka, Trojan, and Rolls/Surrette still makes quality lead acid cells.
What makes lithium ion a worthy candidate to dethrone what practically is an institution in the battery market?
Lithium ion Has Superior Density Over Every Other Type Imaginable
Let us be clear that density is not really a big factor in stationary setups. However, it becomes a crucial factor when it comes to vehicles and other applications that require portable energy.
And in this aspect, lithium ion is king. Overall, if the battery has more energy density in a given area, the better. And research has proved that a lithium ion battery that is only a third of the size of other battery types packs quite more energy density than the said battery types.
It does not matter if its absorbed glass mat (AGM), nickel cadmium, gel, flooded or any other type of lead acid battery. Lithium ion still wins in terms of size, weight, and packed energy.
Lithium-ion is Also More Resilient to Frequent Charge Cycles
All types of energy cells need to be discharged and recharged, and it is this process which is called the battery’s cycle. Lead acid batteries, of course, go through their fair share of charge and discharge cycles, but they are also prone to be worn out sooner, especially when there is just the fact that lead acid batteries can suffer from deep discharging.
Actually, it is these deep discharges that take its toll on the lead acid batteries. If these kinds of batteries are ever to be quickly charged or discharged, the integrity of the battery suffers even quicker, leading for it to be out of commission earlier than its expected years of service.
What’s more, if these batteries are charged below 50 percent, it loses a potential cycle in its indicated available life cycles. Meanwhile, lithium ion batteries can be discharged for up to 80 percent of its state of charge without really suffering any long term effects.
To further illustrate the effects of charging and discharging in a battery, we can go ahead and discuss what is called “the balloon analogy.” You see, charging and discharging a battery can be likened to inflating and deflating a balloon, and several discharge cycles are akin to draining the battery of air and then blowing it up again many times.
Of course, if you do this often enough, you will end up with a balloon material that is fatigued and worn out. It may even tear and have little holes where air can escape.
This is also the case when charging and discharging batteries— the components within can only go through so much charging and discharging before breaking. However, think of lithium ion batteries as having significantly better material than lead acid batteries.
While it also suffers stress from repeated charges and discharges, it wears out a lot slower than lead acid material.T he number of cycles expected to be contained in a typical lithium ion battery is also significantly more than those contained in lead acid batteries.
Flooded lead acid batteries and absorbed glass mat have approximately 200 to 1000 and 200 to 650 cycles stored in them, respectively. Lithium ion batteries dwarf these numbers, containing approximately 1000 to 4000 cycles in its lifetime.
As it is reliable in quick discharge situation, the lithium ion battery also can charge faster than lead acid types. Flooded lead acid and absorbed glass mat are expected to charge from 8 to 16 hours and 4 to eight hours, respectively. Lithium ion batteries can quickly charge back up in 2 to 4 hours.
Those who know stuff about batteries are also aware that an energy cell’s performance in a certain temperature is a good factor in measuring its resilience. Typical absorbed glass mat and flooded lead acid battery usually degrade at over 25 degrees Celsius.
Meanwhile, lithium ion batteries can reliably perform its tasks for up to over 45 degrees Celsius without really suffering any ill effects.
Lithium ion Batteries Have Longer Expected Life Cycles
Lithium ion is kind of expensive compared to lead acid batteries now, but it is not enough to judge battery types by their initial cost. There is a factor called “total life cycle cost” which makes lithium ion worth the expense.
This parameter not only takes the initial cost into consideration. It also factors in the number of life cycles and the depth of discharge to which the battery type can be used optimally. And in this important rating, lithium ion still wins over lead acid battery types.
Consider this: flooded lead acid batteries sure have the lowest lifecycle cost— but this is in the most ideal of conditions. To get the most out of the flooded lead cells, one must makes sure that they perform maintenance checks and procedures regularly.
They also need to make sure that the battery does not often discharge deeper than 50 percent of its capacity. Failing to do these checks will lead to quicker deterioration of flooded lead acid’s battery life, and will thus increase the life cycle cost for this type of battery.
Meanwhile, lithium ion batteries need little to no maintenance. They can also withstand deep discharges, and can handle irregular charging and discharging cycles.
This obviously is a lesser hassle to use than lead acid batteries, and it not only saves time. It also ensures that you get the most out of your battery with the least meticulous maintenance procedures.
Sure, some lithium ion battery models may be more expensive now than lead acid types. However, lead acid had a head start and lithium ion is relatively new technology.
We have stated that typical lithium ion battery models start at US$400 per kilowatt-hour. However, this price can still go down as more and more about the technology is discovered.
Surely, more cost efficient ways of manufacturing and producing the product will be discovered, and by that time lithium ion will truly be the number one choice, replacing lead acid batteries in the process.
A lot of solar energy chargers today are optimized for lead acid operation. However, this does not mean that you should give up on utilizing lithium ion batteries for home off grid use.
Granted, lead acid will work at their peak condition when maintained properly. However, in 2016, there had been a rise in the use of lithium ion batteries for solar charging systems.
It is a best bet to invest in these types of batteries, as they can really have a lasting value in the years to come, when lead acid batteries will be rendered almost obsolete due to the sheer superiority and utility of the lithium ion battery.