I've been using an Antigravity Batteries ATX20-HD Heavy Duty Lithium Ion Battery since April. It doesn't actually have any anti-gravity abilities, as far as I can tell, but it is very much lighter than the stock Banner; and the starter motor has noticeably more vigor.
As far as charging from an alternator, it has a built-in battery management system to control charging.
As far as Li batteries in ICE cars are concerned, I'm not convinced that charging them from an alternator would be optimal, some form of software interface would be essential.
I would agree but for the likelihood that aspect was covered at the outset Peter. For some time now alternator regulation has been taken away from onboard devices and controlled by the ECU which better tailors electrical demands. Changing the characteristics to suit Li-Ion charging would be a relatively simple task involving little or no extra expense.
In the case of Li-ion traction batteries in hybrids, it's likely they are replenished directly from dynamoing motors, regenerative braking etc. not a humble belt driven device.
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
the biggest issue with motorcycle lead/acid batteries is the need for compact size. To get the CCA needed in the smaller size the plates are thinner, which means they simply wear out faster than a larger battery with thicker plates. Regardless, any vehicle that sits for a length of time, should have a maintainer.
Currently I have a bike master Li battery in my three wheeler (that fits my wife's HD heritage softail) as I had it on the shelf when the OEM battery crapped out after 3.5 years and 15k miles (not actually bad for a small battery).
In any case I would only buy a Li battery with an internal control to prevent over charging and total discharging.
Rodger 2018 M3W "Dreamers on the Rise" 2004 Plus 8 (wife's) old Goldwings and a couple of Harleys
where Li batteries outshine (pun intended) lead acid is the ability to deep cycle more often. So if you are using your 12 volt battery to run things without charging at the same time (like my travel trailer when not plugged in), you run the battery down and it has to be recharged, Li batteries can do that many more times than lead/acid. Also Li batteries can hold a charge longer without use than lead acid. Having said that neither Li or lead tolerate deep deep discharges, so many Li batteries have that internal control to turn them off before that happens. Neither tolerate over charging as well.
In your normal car/vehicle the battery is being constantly kept at charge by the engine running. and so should last a long time. However, most motorcycles have really small batteries with small plates and hence they generally do not last long. When you want good cold cranking amps in a light weight small package you loose longevity.
Rodger 2018 M3W "Dreamers on the Rise" 2004 Plus 8 (wife's) old Goldwings and a couple of Harleys
If you have ever seen one of this portable jump start power packs in action it would make anyone a believer. Sit in the trunk of your car for lord knows how long and then asif by magic it stars a dead batteried car.
The light at the end of the tunnel is actually a train. 2019 M3W