Q What makes Shorai LFX different from other batteries?

A Shorai LFX batteries contain Shorai-proprietary eXtreme-Rate Lithium Iron prismatic cells (chemistry LiFePO4). Shorai LFX contain no poisonous lead, no dangerous acid, and do not create explosive gasses during charge, as traditional Lead-Acid batteries do. Compared to lead-acid, Shorai LFX lithium are also extremely light, have much lower self-discharge rate, do not sulfate (i.e. do not degrade while sitting unattended), and are environmentally friendly.

While there are other companies now offering Lithium-Iron based powersports batteries, all except Shorai use cylindrical cells originally made for power tool applications. Such cells are inferior to Shorai Prismatic LFX, for several reasons.

First, the cylindrical cells come only in one size, so that the possible shapes and sizes of the starter batteries they make are very limited. As such, battery fit into many vehicles may be poor, or impossible as they are too wide, or too tall. LFX prismatic cells, on the other hand, are rectangular packages which we can freely design and size according to the size requirements of the battery case. As such, Shorai LFX offer perfect drop-in fit in many vehicles and - if the LFX is slightly smaller in one dimension - high-density, adhesive-backed foam shims are included in the package. These can be applied to the battery box in a few minutes, to insure a perfect “as original” fit. No saws, cutting torches, or duct tape required!

Second is the pedigree. While power-tool cells may crank a vehicle successfully, they were not originally intended for the high current discharges in starter systems. As a result, cranking performance suffers compared to Shorai LFX, and the batteries will wear out more per every start. By contrast, Shorai LFX are the result of years of our own research and development, and are designed and produced in our own tightly controlled factory. Shorai LFX have been used in some of the most extreme high-current projects in the world, including autonomous aircraft, boats, and submarines, electromagnetic rail gun research, and more. In short, LFX have been designed from the “ground up’ to be a powersports starter battery with long lifespan and high performance, under a wide range of temperatures.

Finally there is quality control. Every Shorai LFX is built in our own ISO 9000:2008 certified factory. The primary cell ingredients are sourced from Japan, which allows us to produce the most consistent and reliable cells. Then we do individual cell quality control and matching over a six-week period, for every cell we make. This test period is two to four times longer than typical and is expensive for us. But it is worth it, in terms of product quality in the long run.

Q Why are Shorai LFX priced below other lithium starter batteries?

A Shorai LFX batteries are produced exclusively in our own dedicated factory, in large volume, by an experienced production team. The resulting high yields reduces our costs, and the factory-direct connection allows us to offer pricing which is competitive with traditional OEM lead-acid batteries, and lower than any other lithium-based alternative.

Q How does the LFX "PBeq AHr" capacity rating compare to lead-acid Ahr ratings?

A First, we need to understand that the primary job of a starter battery is to flow a large current (amperage) for a short time, in order to start a vehicle. In order to do that efficiently, the battery must have low internal resistance. Holding all other considerations equal, the larger the battery is in capacity the lower the resistance, and the better able it is to crank a vehicle under high loads.

Lead-acid makers have therefore used AHr(capacity) ratings as shorthand to indicate cranking ability, rather than a real usable capacity. The lead-acid capacity rating itself is based on a complete discharge at a low discharge rate. Under actual cranking conditions they will deliver considerably less than spec capacity. And because lead-acid batteries begin sulfating when only a small percentage of the capacity has been used, and their internal resistance rises as they are discharged, the actual capacity which can be USED may be as little as 20% of the mfg. rating. Discharge in excess will not only damage the lead-acid battery, it may not allow proper starting as voltage sags.

Shorai LFX are based on a completely different chemistry. Not only do they have less than 1/3 the internal resistance per capacity than do lead-acid, they are also the ultimate "deep-cycle" battery. The internal "completely discharged" capacity of a Shorai LFX is 1/3 the rated "PBeq" capacity. For example, the LFX18 12V series have 6Ah cells internally. But the cells are capable of 90% discharge without damage and while retaining more cranking ability. As such, the USABLE capacity(or "reserve capacity") of an LFX18 12V battery is on or very near par with 18AHr-rated lead acid batteries, while providing superior cranking performance and a vast reduction in weight. The Shorai PBeq AHr (lead-acid equivalent) rating system therefore allows users to compare a very different technology from lead-acid, but on a close apples-to-apples basis when making a choice.

Q How does the LFX "CCA" cold-cranking rating compare to lead-acid Ahr ratings?

A CCA ratings another way that lead-acid makers have tried to convey starting power. Unfortunately, their typical spec is based on a "half-nominal-voltage" delivery. That is, at their CCA spec, you can expect 7.2V delivered, at best; and 7.2V isn't useful, as you won't start a vehicle with it... In any case, CCA ratings aren't about actually drawing that much current from a battery. The typical vehicle which uses a 200A CCA-rated battery, for example, will only draw 45A~80A from the battery. What the CCA rating really intends to convey is how much voltage will be delivered. Higher CCA rated batteries will deliver more voltage at the same actual cranking current. Our LFX are CCA rated to deliver 9V for a 5-second crank at the CCA rated current. (in fact, our average voltage delivered will be even higher during a 30-second crank. But our CCA ratings are intended to indicate not only a measure of voltage at true cranking currents, but also proper usage, which lead-acid do not) At actual cranking currents - which are always well below CCA, LFX deliver up to two volts more than an equivalent-CCA-rated lead acid battery. Current alone won't start anything. It is the current multiplied by voltage that does the work (watts). In reality, this means that you can multiply the LFX CCA rating by 1.5x to compare to a Lead Acid battery CCA. For example, our 270A CCA LFX18 series provides about the same cranking voltage as a 405A-CCA-rated lead acid battery (from a quality lead-acid maker; some CCA specs we've tested on the cheapest lead acid seemed to be plucked from thin air).

About Shorai LFX