CW Evaluation: Shorai Lithium Iron eXtreme-Rate LFX Battery

After two years, it’s still everything it’s cranked up to be.

Shorai Lithium Iron eXtreme-Rate LFX Battery

Product Review: Shorai Lithium Iron eXtreme-Rate LFX Battery

Pity Burns's poor old R1, abandoned for weeks on end to sit home while shiny new testbikes get ridden instead. Well, if it sits home, it's not so bad, because then it gets plugged into the trusty battery charger. But if it gets left where there is no charger, sometimes the old girl just doesn't want to crank over.

Enter the Shorai Lithium-Iron battery. With a self-discharge rate claimed to be 1/6 to 1/7 of the typical lead-acid battery, a fully charged LFX can sit for many months and still retain adequate starting capacity, provided your bike doesn’t have a clock or other accessories that draw current when the key is off. And since the LFX doesn’t sulfate as capacity drops, it should still crank away without hurting itself, even if the remaining capacity is quite low.

Other companies offer Lithium-Iron-based batteries, but Shorai says they’re all made up of cylindrical cells originally produced for power-tool applications and, as such, are inferior to Shorai’s “Prismatic LFX.” Shorai makes rectangular cells, however, designed and produced in its own factory to fit in batteries sized specifically for motorcycles. And since power-tool cells weren’t intended for the high current discharges in starter systems, they’ll wear out more quickly, claims Shorai.

Procrastination is a good thing when "battery testing." The Shorai, delivered with a 90-percent charge, sat on Burns's desk for a month before being transported for transplant. Sure enough, the R1's neglected lead-acid battery could crank the engine just fast enough not to start it before giving up the ghost. Yanked from its resting place and placed upon the postage scale, the old battery weighed in at 7.8 pounds, while the new Shorai is just 1.85 lb.! Not only does it weigh 6 pounds less, the Shorai also is smaller, and its box includes an assortment of adhesive-backed foam rectangles to make it a snug fit in any battery box. Shorai even provided two sets of nuts and bolts, for people prone to dropping things. We only needed three.

Once ensconced and hooked up, the new battery spun the R1 starter like it’s never been spun before and fired up the engine immediately (in spite of yet another clogged pilot jet from modern gas and failure to Sta-Bilize). Two weeks of sitting later, same story.

Shorai says hooking up a battery tender is unnecessary but won't hurt anything, provided the charger does not have an automatic desulfation mode (the popular Deltran "Battery Tender" does not). Another six weeks of sitting later (with Sta-Bil in the tank), same excellent cranking power. Now, after about a year-and-a-half of use and no time on the charger, the Shorai can be depended on to fire the beast after months of neglect. Chilly SoCal mornings with temps in the 30s slow its cranking not a bit; neither does throwing the battery in the freezer overnight.

Now for the downside: The LFX for a 2000 R1 sells for $159.95, just about twice what you’d pay for a normal battery. Shorai has backed off from its claim that an LFX battery should last 5 to 6 years, and up to 10 under ideal conditions—just because it hasn’t been around long enough to prove that claim. But it is confident its lithium-iron battery will outlast a conventional lead-acid one. Hopefully, Burns’s R1 lives long enough to let us know.


**Shorai Inc.

845 Stewart Dr. Ste. D

Sunnyvale, CA 94085




  • Instant 6-lb. weight loss for our R1

  • No more fooling with battery chargers, supposedly

  • No lead, no acid: OK for kids to lick


  • Twice the price of a regular battery

  • There are no more downsides