Previous owner installed a super light and small Lithium battery to replace lead/acid battery. Since it is small, there is a lot of room to shift around so I bought an industrial strength velcro and attached to the bottom. Nice and secured now!

Be careful about those small lithiums.
Never make mistake I did and leave lights on without bike running...

Yup, thanks for the warning.

Those lithium batteries use LiFeCO4 (lithium-iron) chemistry and has much, much higher output current than lithium-cobalt batteries used in laptops. They don't have thermal-runaway issues laptop batteries have either. However, for size, they have less capacity.

Along with most of them not having over-discharge protection means you can run them down very quickly. I used one on my race-bike for years without any issues. One great benefit is no self-discharge like lead-acid batteries. I left it over winter out in cold and 6-months later, it started up bike just fine! :)


Then I got similar lithium battery for race-bike and moved old lithium to street bike. However, one time I parked in driveway and walked down to get mail. Talked to neighbor for 5-10 minutes max. When I came back, I found I had left headlights ON! Drained battery down past recharge point. It was dead, pakut! Couldn't charge it back up.

I've been searching for lithium battery that has over-discharge protection and it doesn't appear anyone makes one. I'll just add an external cut-off circuit that'll disconnect battery when it drops to critically low voltage.

I would have to check which type I have.
Brand Name = BatteryTender.

One great benefit is no self-discharge like lead-acid batteries. I left it over winter out in cold and 6-months later, it started up bike just fine! :)

I've never had a battery in my H2 prevent it from starting, no matter how long it was parked, even if I left the headlight on and ran the battery down to zero. :)

Quick question to the OP regarding the lithium battery. Do you by chance know how much lighter it is than the OEM lead acid?

Quick question to the OP regarding the lithium battery. Do you by chance know how much lighter it is than the OEM lead acid?

I did not really weigh it but by hand, it felt like it is, at least, 1/3 lighter ... may be more.
But, it's physically smaller so you need to attached industrial-strength velcro so it does not shift around.

Quick question to the OP regarding the lithium battery. Do you by chance know how much lighter it is than the OEM lead acid?

Saves about 7-8 lbs over stock depending upon whether you had flooded cells or AGM battery.