Lithium battery transition

[Marvin2Shoes]

2011 RT.... Has anyone had any luck finding a lithium compatible regulator /rectifier for this year model as 2013 onward seems to be well catered for?

[David.]

Could this be because the regulator/rectifier is an integral part of the alternator on a Camhead.

Why do you need to change the regulator/rectifier.

This is a 2018 R1200GS, the guy didn't change anything other than the battery.

[Marvin2Shoes]

I believe some better lithium batteries have a good quality bms built into the battery. Apparently the cheaper ones don't. I was wanting to change to lithium because they last 10 to 15 years. Much more than the gel battery @ 7 years and the lead acid at 5 years (good quality versions of each).
Lithium don't drop voltage as much under load as the others which seems to be preferable given the seemingly prolific BMW canbus reporting of 'undervoltage' errors.
As the alternator has the reg/rect integrated (Haynes manual) I decided to check if the excitation voltage was computer controlled or handled internally also. The D+ line originates in the ZFE unit. This likely stops any changing of the alternator to allow a lithium battery in my 2011 model RT.
SO TO RECAP: No LED lights unless canbus compatible, no aftermarket brake flashers, questionable upgrade path to lithium battery. Is there any modification that can be done to these machines?

[David.]

This likely stops any changing of the alternator to allow a lithium battery in my 2011 model RT.

Why does the alternator need to be changed.

I believe some better lithium batteries have a good quality BMW built into the battery.

Does the BMS not look after the battery, https://www.motorcycle.com/products/lit ... -realities

[David.]

More info. here, https://fulbat.com/wp-content/uploads/2 ... um_PDF.pdf

[Marvin2Shoes]

Why does the alternator need to be changed?

Ideally a lithium compatible reg should be used to charge a lithium battery. When the alternator has an integrated reg and that alternator has no upgrade path to lithium reg available the option is to replace the alternator with an alternator that has the lithium reg. At least that is the way I see it happening.

Does the BMS not look after the battery?
Yes... If fitted, otherwise a lithium compatible reg would, imo, be required to ensure battery charge is within acceptable parameters.

[David.]

Buy a lithium battery with a BMS, fit it to the bike, job done.

[Marvin2Shoes]

Well if it's that easy why would anyone bother with gel or lead/acid?

[David.]

What is the cost of a lithium battery vs gel or lead/acid.

[Marvin2Shoes]

Seeing that most people are getting pretty short life from their gel batteries the AU$160-240 for a decent lithium battery sounds like a good deal. I have lithium AA batteries I purchased in 2010 that are still going strong.

[David.]

My most recent GEL battery has now been in service for 4 years and cost £67.

[Marvin2Shoes]

Gel @ £67 for 3 to possible max 7 years service
Equates to £22.00 to £16.40 per year
Versus
Lithium @ £114 for 10 to possible max 15 years service
Equates to £11.40 to £7.60 per year
Therefore gel isn't just more weight on the bike, it's significantly more hefty on the back pocket over the life of the battery.

[David.]

Fair enough, are you going to get one. I can't find a lithium battery in the UK for £114.

At £250, this is the equivalent replacement battery for an Exide GEL12-19, https://www.mdsbattery.co.uk/shorai-lfx ... ttery.html

[Elkinell]

Fair enough, are you going to get one. I can't find a lithium battery in the UK for £114.

At £250, this is the equivalent replacement battery for an Exide GEL12-19, https://www.mdsbattery.co.uk/shorai-lfx ... ttery.html

Bit the shed - 'ow much? Not going to happen in our house - I'd be fitting a rat on a tredmil before I paid that for a battery.

[David.]

The Exide GEL12-19 is now £75 from Tayna Batteries, https://www.tayna.co.uk/motorcycle-batt ... ide/51913/

or

£280 for this Bosch Lithium alternative, https://www.tayna.co.uk/motorcycle-batt ... 3-lithium/

At just over £40, this Numax battery is the cheapest in the 51913 range from Tayna, https://www.tayna.co.uk/motorcycle-batt ... /nts51913/

Would the Bosch Lithium last 7 times longer than the Numax AGM. Don't forget to add the cost of a Lithium battery charger.