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Q. How do I maintain my Shorai LFX Battery?

Dr Shock Says "It's not hard to maintain your LFX properly!"




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.







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Q. Will a Shorai LFX Battery Work In My Custom Vehicle?

Our batteries will generally work in vehicles up to 110 Cubic Inches or 1,800 Cubic Centimeters (LFX36L3-BS12 and LFX36A3-BS12 series).  If you have a stock motor pulled from another vehicle, then you can use our battery finder to select the battery that the motor came from as long as the starter gearing is the same.  If you have any other questions, please give us a call and we will assist you.

Q. Will a Shorai battery work in my vehicle?

A. The short answer is yes! Shorai batteries are an easy drop-in replacement upgrade.  Your vehicle charging system should be working within standard spec (generally that means charging at 13.6-14.4 volts when running), and please use our Battery Finder to select the correct battery for your vehicle. Call us for a recommendation if you don't see your vehicle listed or if you have a custom built motorcycle.

Q. What is the Difference between your Standard and Duration Recommendation?

Standard recommendation is meant to provide the same starting performance and capability as the OEM equivalent battery.

The Duration recommendation is more suited towards vehicles that are ridden less often, have more accessories, a modified engine and/or charging system.  We always refer to the Duration battery for those who want the strongest possible cranking performance and lifespan from Shorai LFX batteries.

Q. What is the best way to facilitate long term storage?


Dr Shock Says "Stay Cool in STorage, for a long, long life..."



A. Cool storage is good for any type of battery.  You may remove the battery from vehicle for summer storage and place in a cool, dry location – with terminals taped to avoid short circuit (ideal is
about 34F/1C, so a refrigerator is great).  Avoid storage at temperatures below 0F/-18C or above 90F/32C whenever possible.  Any charging during storage should be performed at temperatures above freezing, for best results. If you want to keep the battery in the vehicle during storage, but are uncertain when you’ll ride next, a Shorai BMS Charger connected in Store Mode is the best choice to maintain battery charge.  An hour before riding, unplug the BMS charger and disconnect from wall power, then reconnect and start Charge Mode to fully charge and balance the battery.




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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 more capacity a battery has the lower its resistance will be -- thus it will be more able 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 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.


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Q. Addressing Water and Corrosion?

Sealant and Grease locations for the battery

Dr Shock Says "Keep it Sealed and Greased...WhooHooo!"

A. WATER/CORROSION: Avoid high pressure power washing around the battery case, or constant exposure to water.  If the battery may be occasionally submerged, we highly suggest application of sealant to fill the horizontal seam between top and bottom of the battery case, and that the 5-pin port be fully packed with dielectric grease. (dielectric grease is a good idea in any case to insure no pin corrosion).  Also, heavy grease should be liberally applied to terminals for wet environments




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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).



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Q. Can I use Lead-Acid battery chargers or charger/tenders?

Voltage and Remaining Capacity Diagram





A. Yes. HOWEVER, you may NOT use a charger/tender if it has an automatic "desulfation mode", "repair", "recondition", or "recovery" mode, which cannot be turned off.  Lead acid charger/tenders can be used for regular maintenance charging and then be disconnected after the battery is fully charged.  DO NOT leave the lead acid charger connected to store the battery, because most will NOT maintain the proper voltage for lithium batteries.  IMPORTANT- if the LFX battery is deeply discharged below 12.86V a lead acid charger/tender should not be used to recover the battery (balance charging with a BMS-01 is recommended) 

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.






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Q. What about Safety Precautions?

Dr Shock Says "Hot Dang!  Don't short the terminals!"


A. Starter batteries of any type contain a large amount of energy.  During a short circuit, ALL that energy is released in a matter of seconds, creating an extremely hot arc welder, possibly causing fire or explosion. You MUST be very careful at all times to avoid short circuit of the positive and negative terminals.  Do NOT wear jewelry on wrist or neck while handling batteries. INSURE that when installed the positive and negative terminals are properly covered and insulated from the vehicle.  Do NOT use carbon fiber battery hold down units, as carbon is an electrical conductor. When replacing a battery, its important to verify that your charging system is working properly and the output voltage is within the recommended range of 13.6-14.4v. At no time should the charging system output be above 15.2v or it can damage the battery.


Q. Will Shorai LFX Batteries Work In My Electric Vehicle, total loss vehicle, or Non Vehicle-Starting Application?

A. First of all, please note that our batteries have been formulated, revised, and updated many times in order to improve performance in every aspect of performance for their intended usage as powersports drop-in upgrade batteries.  Due to safety precautions, please note that our warranty does not cover total loss or capacity usage.  Lastly, please see the FAQ Question: "How does the LFX "PBeq AHr" capacity rating compare to lead-acid Ahr ratings?" for further information.

Q. Cold Weather Performance Expectations?

Dr Shock Says "BRR Warm me up!!!"


A. 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. Am I covered under warranty?

Dr Shock Says "Do I Qualify?"




Please visit 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. Use in aircraft, automobiles, and motive power applications are not recomended  and will void any guarntee or warranty.  If your LFX™ battery is not recommended for your vehicle, contact your seller to exchange it for the proper battery.  Please visit for warranty terms.