Stark Power LifeP04 Ultrastart Lithium Motorcycle battery

I decided to look into a new battery technology not because my lead acid was not doing something for me but more so that I wanted a battery to do more for me. I looked into several companies and settled on Stark Power (starkpower.com) and their UltraStart series.

A little bit about lithium batteries. They are not all the same and there is some major differences between them. Stark Power uses LiFeP04 which is a Lithium Iron Phosphate as apposed to LiPo or Lithium Polymer. LiPo is a common battery in the RC car and plane world and is known for being the "dangerous one" because it can catch fire during charging, release gasses, puff up or just get very hot. LiFeP04 on the other hand is considered the safest Lithium battery and has many advantages over other forms of Lithium and Lead/Gel/AGM batteries.
LiFePo4 out perform many of the competition because of how they discharge their power. They can typically use 100% of their storage capability (Amp-hour) vs a typical lead-acid battery uses only about 30% of its available power. LiFeP04 also maintain their voltage better during amp draw as opposed to a traditional battery lowering it's voltage as the amperage draws down. However, when a LiFeP04 battery is depleted, the cut off is abrupt. When you compare Amp-Hour ratings, 2AH for the LiFeP04 is equivalent in capacity to 6AH for a Lead-Acid battery.
Some other bullet points on the LiFeP04 are:
Cell Cycle Life: 20,000 shallow cycles
•Longer Life Cycles: Exceed 2,000 full cycles, 5 times better than Lead Acid
•Higher Discharge Power: 6.6 times of Lead Acid
•Less Charging Time: Less than 2 hours
•Less Self Discharge Rate: Less than 8% monthly, Lead Acid is 20%
•Less Weight and Size: 50% or better of Lead Acid
•High Temperature: Can operate at 70°C without life degradation
•Low Temperature: Can operate in -30°C with slight performance degrade
•Maintenance Free: Flooded Lead Acid need constant distilled water maintenance
•Lithium does not Freeze
•Safer: No Explosion, No Fire
•Non Toxic to the Environment
•95% Energy efficient

Here are some comparisons of the 2 batteries from a size and weight standpoint.
When it comes to weight, the LiFeP04 is amazingly light. My old battery was over 11.5lb and the Stark is under 2lb. When you look at that from a center of gravity stand point and also remember that the Stark battery is close to 3" shorter this make a big difference. Mathematically, it has been shown that 7lb of weight reduction can be equal to approximately a 1hp gain. No bad.

Another area of interest for this battery is that it has a built in microprocessor or Battery Management System (BMS) This continuously monitors each cell's voltage and can transfer voltage from one cell in the battery to another to maintain balance. Each one of StarkPowers batteries come with their own charger and charge port cord. You must use their charger to maintain proper battery life though.
One of the coolest features of the UltraStart series of batteries is their "IQ Restart Technology". Basically, if you leave your lights on, stereo playing or whatever drains your battery down to the point of normally not being able to start your bike the battery will sense when it is low and will cut off all power and leave enough juice to restart your bike. All you have to do when this happens it cycle the key off for 2 seconds and the bike will start normally. To test this I needed to drain the battery down but since our bikes don't keep the lights on when the motor is off, I had to get creative. With the key on, I rigged the brake lever to stay on, turned on my LED under bike lights, plugged in a 12V air compressor with road safety light to my charging port and just waited, and waited and waited. I had a digital multimeter monitoring the battery voltage and finally after about 40 minutes of waiting with very little voltage drop, I decided I needed to load down the compressor to draw out some amperage from the battery. I started filling an air tank that caused the compressor to lug down and draw a lot more amps. When the battery voltage reached 12.1V as shown on the multimeter, the battery cut all power and shut everything off. I then turned the key off for 2 seconds and then back on and the bike fired right up! Great piece of mind to have. Here is a picture of the compressor and lights on trying to drain the battery down.
Here are some other comparison shots of the batter installed in the bike. You can see that the Stark battery is much shorter and sits lower in the bike. One note, the Stark battery has 4 threaded lugs or posts and each post is threaded on three sides so hooking up accessories is a breeze. I did have to use a spacer as the Stark lugs are wider than the stock battery but the company confirmed that they will be changing their post size to a more standard size in the very near future.
This battery retails for around $220 but when you consider the advantages in technology, life expectancy, weight savings and that price includes a charger, I think it's a great deal. I look forward to seeing how it performs over time but have a hunch that there won't be much to report back on with this one. So far, I'm very happy with my choice.
The entire write up with comments can be found here.  http://www.riderforums.com/general-mean-streak/80859-stark-power-lifep04-ultrastart-battery-review.html