Q. How do I maintain my Shorai
A. LFX™ batteries should be
recharged whenever voltage drops to 13.1 volts, or sooner.
If you have a vintage, custom, or off-road vehicle which has NO
draw on the battery when key is OFF, then you should only need
to charge your LFX™ battery once a year.
However, most modern street bikes have
a draw even when key is off, to support clock, computer, alarms,
or other devices. This draw will eventually drain the battery,
which is damaging and could void your warranty. So if you are
not riding twice a month, then you should charge the battery
every few weeks. “Smart” lead-acid
chargers with automatic cutoff may be used for periodic
charging, but will NOT work as a tender/maintainer and should be
disconnected immediately after charge has finished.
Older lead chargers without automatic shut-off should never
be used. Improper charging is dangerous and
will void your warranty. A Shorai BMS Charger - with Store Mode
- is highly recommended for anyone who rides less than twice a
month. Alternatively, you may disconnect the negative cable from
the battery for storage, and charge once per year in that case.
Q. What makes Shorai LFX different from
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
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originally made for power tool applications.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
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
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
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
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 80% 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).
Q. Can I use Lead-Acid battery chargers
A. Yes. HOWEVER, you may NOT use a
charger/tender if it has an automatic "desulfation mode", which
cannot be turned off. We have confirmed with Deltran, makers of
the "Battery Tender" brand, that their products do NOT have a
desulfation mode, and are therefore OK for use with Shorai LFX,
for example. But the best possible charger/tender for Shorai LFX
is the SHO-BMS01, which will be released on about March 15th
2011, we expect. It uses the 5-pin BMS port in the LFX
batteries, in order to monitor, diagnose, and balance the
individual cells during charge. And it also has an optimized
storage mode that will give the longest possible service life to
If you are storing your vehicle and want to check the remaining
capacity, or you're a racer with a constant-loss system, you'll
want to know how resting voltage (i.e. with no load or load
under 200mA) maps to remaining capacity. LFX batteries should be
maintained such that 20% capacity remains at minimum, as best
practice. Use a good-quality voltmeter to check remaining
capacity, and consider recharge whenever the battery capacity
falls to about 50% remaining. Of course, if you get the Shorai
dedicated BMS01 charger, you can just hit the "Store Mode"
button and leave it to do the work for you.
Q. Should I use a battery tender?
A. The short answer is "only if you
really need to". Most powersports enthusiasts have gotten used
to hooking up a tender to their lead-acid batteries, all the
time. Shorai LFX have much slower self-discharge than the best
lead acid do (1/6 to 1/7, on average), they do not sulfate as
capacity drops, and they are the ultimate "deep cycle" battery,
which means that they can still crank your vehicle even if the
remaining capacity is quite low. Therefore most riders will not
need to use a tender at all. Even a charger or tender uses
energy you have to pay for, and there is always the possibility
that a charger or tender can fail in some way, so if not really
needed the best practice is to not use one.
A fully charged LFX can sit for a year or more and still retain
adequate starting capacity, without damaging the battery. As
such, any vehicle which has no current flowing when the key is
OFF should never need a tender. At most it should be charged
every 6 to 12 months, depending on the average storage
temperature (cool storage is much better for any battery). Many
older vehicles and most dirtbike/atv fall into this category.
Newer vehicles may have a significant draw even when the key is
OFF, to maintain clocks and computers, etc. In this case we
expect that a few hours of riding per month will be all that is
needed to avoid tending. If you know that you will go a number
of weeks or months without riding, you can either attach a
tender, or disconnect the negative cable from the battery. In
any case, during storage you may use the voltage chart above and
an accurate voltmeter, and consider recharging when the battery
is around the 50% capacity remaining mark, or above.
Q. I hear that lithium crank poorly
when it gets cold, is that right?
A. Lithium do increase in
resistance more as temperature drops, compared to lead-acid.
However, they also react to cranking under cold conditions in a
much better way.
Down to about 20 degrees Fahrenheit (-7C) most
users find that they can start normally on first crank. If your
headlight comes on at key-ON, it is good for the batteries to
flow some current before cranking in cold weather. The suggested
headlight-on time before cranking depends on the temperature. If
starting at 40F/5C, 30 seconds will help wake the battery and
increase cranking performance. If at 0F/-17C, leave the lights
on for 4~5 minutes before cranking. The result will be a better
first crank, and longer battery life. If the engine fails to
start on first crank, that first crank has warmed the battery,
and the second attempt will be much stronger. Other accessories
that can be turned on before cranking can also be used for this
purpose, such as heated gear, radio, etc... Insuring that the
battery is fully charged after storage also improves first-start
performance in cold weather.
Q. Can Shorai LFX be fully discharged
and then disposed in regular garbage?
A. That depends on your municipal
regulations. Shorai LFX meet the European RoHS standards for
environmental health, and contain no lead. Check with your local
authority to see if LiFePO4 batteries are allowed. If so, fully
discharge the battery before disposal, using a 12V light bulb
until no longer lit, for example. We expect that there will also
be recycling available in some locations, and more coming in the
Q. Can Shorai LFX be mounted in any
A. Yes. There are no liquids in the
Q. How long will my LFX battery last?
A. That depends on many factors.
Under the worst conditions, a lead acid battery may last only a
few weeks and under the best about seven years (top-quality
brands with regular use). In between you will find a wide
variety of user experiences. Our research indicates an average
of about 2 1/2 to 3 years lifespan for lead-acid. Under the same
average usage conditions, we expect Shorai LFX to last roughly
double, or 5 to 6 years. Under ideal usage and storage
conditions, we expect 8 to 10 years to be achievable. Due to
their lack of sulfation and slow-self discharge, Shorai LFX
increase battery life most for users who sometimes store their
vehicles for weeks or months at a time, and don't want to or
can't use a battery tender.
Q. The terminal screws seem too short
for my vehicle, which has thick cable eyelets. What can I do?
A. First, see the install guides on
our site. They show how to use the foam padding (5mm shown, but
10mm sections may be even better) on the nut bottoms, so the
nuts rise to the top of the terminals. This helps the screw
threads catch the nut. If that isn't enough, note that the
screws are M5x0.8 pitch. Any hardware store should have a
selection of those, so take a terminal screw to compare and get
slightly longer screws, as well as some washers to make sure
that the screw doesn't penetrate "too far" when tightened down.
We should also have longer screws in stock by Feb 2011, for the
rare times when they'll be needed.
Q. Am I covered under warranty?
A. Please visit http://shoraipower.com/
PRIOR TO INSTALLATION and use our year/make/model finder to
verify that you have purchased the correct battery for your
vehicle. Use of an incorrect battery in your vehicle can be
dangerous and will void any guarantee or warranty. Batteries are
not covered under usage in electric vehicles. If your LFX™
battery is not recommended for your vehicle, contact your seller
to exchange it for the proper battery. Pleave visit http://shoraipower.com/customer-service
for warranty terms.