Lithium-Ion Batteries

[suecanada]

I happened to revisit the Euromotoelectrics website yesterday. I bought LRB's 400 watt alternator upgrade from John Rayski there. Well, I noticed that he cautions that a lithium-ion battery cannot be used with his alternator upgrade. Shorai is the only brand name I know of for such an animal. It is advertised in Cycle World. Just wonder why there is an incompatibility? I will have to ask him. Any guesses or 'fer sures' out there?
FYI the euromotoelectrics upgrade replaces the voltage regulator and diode board with a regulator/rectifier mounted near the battery box and has a brushless alternator. This help?

[Crossrodes]

Sue go here and see what the Goldwing riders have discovered about these batteries:

http://gl1800riders.com/forums/showthread.php?304577-Shorai-battery-Freds-post

I don't think it is a good idea to use them at this time because of their short life.

[Barry]

I look after 130 laptops that use lithium ion batteries at work. The laptops have a 5 year replacement cycle which means at least 1 new battery so I buy a lot of them and get to know how long they last under different conditions. It doesn't surprise me that they may have a short life in automotive applications.

They are very fussy about charging conditions and need a highly regulated charger which is unlikely to be met in automotive use without an adjustable voltage regulator.

Like lead acid they do not like  high temperatures which shortens their life dramatically - One teacher keeps his laptop on top of a heater all day and wonders why his battery doesn't last !!!

This may sound counterintuitive but unlike lead acid they do not like being fully charged all the time and last longest when kept in a partially charged state. That's not going to work well in a regularly used automotive application. If you want to shorten the life of the battery in your new laptop operate it on mains from day one and never cycle it.

If you want the laptop battery to last; fully cycle it a few times from new and thereafter only partially discharge it before charging again. Also if you regularly use the laptop on mains all day long; discharge the battery to 50% then take it out and put it on the shelf until needed. Likewise if you only use the laptop occasionally store it with a 50% charge in the  battery.

[suecanada]

I think there are some lessons here for our Garmin GPS's?? Especially me who doesn't use the GPS all winter long! So as the GPS sits in storage, I should only periodlically take it out and put it on the AC adapter? How often during the 6 months it is stored in a drawer should I take it in the car for a full charge, Barry? If the GPS was yours Barry what regimen for battery longevity and care would you do?

[Barry]

Lithium ion batteries have a very low self discharge rate if stored in a cool place so at most I would only charge it once over a 6 month period. But I would not fully charge it. The idea for maximum battery life is to maintain the battery approx. 40% - 50% charged.  So at the start of the storage period charge (or discharge) the battery to 50% which over a 3 month period would probably only drop to 40% assuming the device has no quiescent current draw. You would then need only a short boost back up to 50% again. This regime is seeking perfection though and it's not realistic to achieve that with a portable device battery.  It's probably far more important just to remember not to long term store a lithium ion battery in a fully charged state than worry about maintaining it at exactly 40% or 50% charge.  

Oddly enough I'm typing this on a 7 year old laptop which still has a usable original battery because the Teacher who had it for the first 5 years very rarely used it and didn't worry about fully charging the battery before storage.