Hi Zissou, I am not an expert BUT I have already made the swap from the stock Yuasa to the Shorai Lithium-Iron-Phospate in my 2013 Monster 1100 EVO ABS
The stock battery is the specific Yuasa model YT12B-BS. The one I pulled out is branded Yuasa, not Ducati, and has that model number written on it. On the battery itself, specs are 10.5 Ah, and 210 CCA. As far as I can tell, dimensions are as per their website at http://www.yuasabatteries.com/batter...=B168&vID=6505
although they quote 215 CCA... slight change in manufacturing maybe?
I ditched the battery to try to improve cold starting, I was getting high 12, low 13 volt on rest but it needed to be plugged into the battery tender (I had a battery fighter junior) EVERY NIGHT. Bear in mind that the immobiliser, computer clock etc will draw power when the bike is off. The battery was 2 years old.
By the way, based on previous purchases of new lead acid batteries, they ship with the acid separate and you have to fill them and do a long initial charge. Often the dealer will do this for you.
If you wanna replace, you need to match the size (equal or smaller all around) and polarity. Some posters have gone for much higher spec batteries which might be taller, but I wanted to ensure that all cabling would fit like stock.
I put the Shorai LFX18A1-BS12 in as a replacement. Specs are here: http://shoraipower.com.au/store/products/lfx18a1-bs12/
This battery is slightly smaller all around than the Yuasa, but the Shorai arrives with a bunch of padding you can cut up to make it fit. FYI I did find the battery ended up a little wobbly as it sits up higher in the battery tray on top of the padding. I have had no troubles with it rattling or anything like that. The padding lifts the battery up so that the terminals end up in the stock position.
Anyway, there is much info on the Shorai web site... short version is that it's hard to compare given the very different chemistry BUT the battery is rated as equivalent to 18 Ah, 270 CCA. Shorai suggests it will crank like a lead acid battery MUCH higher rated (like 400 CCA plus). The battery weighs like 2 pounds as against 7 for the Yuasa !
I believe the lithium specific tenders don't have float charge on them like normal ones and they ABSOLUTELY don't have high voltage desulphation modes. You can actually use a normal charger to charge the Lithium BUT
* the Shorai arrives mostly charged, you can just go for a ride after installation to top it up
* you need to pull the charger off after the charge - ie, DONT use the float charging
* my tender wouldnt charge the Shorai - the Shorai was already too well charged
In fact, the local Shorai agent advises just ride the bike at least once every couple MONTHS (!) to keep it charged. I ride weekly summer or winter so I have NEVER charged the battery since I installed it! Anyone wanna buy a cheap battery tender?
I dunno if lithium tenders work on lead batteries - FYI the Shorai has a special charger (if you need it; I don't own one) with a special 4-pin plug, so it would not plug in to anything else anyway.
ALSO: you can also upgrade the starter circuit cables with the kit from Motoelectric, I have done this also. Details here: http://www.motolectric.com/products/hicap.detail.html
For me, this was quite an involved installation but rewarding. I could provide some tips maybe later.
and finally: with all of the above the bike will start, from cold, 0.5 seconds every time. Even in Winter (though it only gets down to about 5 deg C here).
with NO external battery charging EVER
PS> I do have one more trick that's helping to get reliable cold starts on my bike. After I switch on, and the fuel pump runs its priming cycle, I give it another prime - I hit the start button with the kill switch set to OFF for 2/3 seconds. Then set the kill switch to RUN, then it will light up first time every time.