Don’t pack spare Lithium batteries in checked baggage after 1/1/2008

According to this US Government site, spare batteries should be packed in carry-on luggage only. Here is the table that appears on the official website.

 

GUIDE TO RULES EFFECTIVE JANUARY 1, 2008
Type Of Battery/Batteries
In Checked Baggage
In Carry-On Baggage:
Lithium Metal Battery, Installed in a Device (up to 2 grams lithium)
Permitted 1
Recommended 1
Spare Lithium Metal Battery (Not Installed In a Device) (up to 2 grams lithium)
(up to 2 grams lithium)

Forbidden
Permitted in carry-on baggage 2
Lithium Metal Battery, Spare or Installed
(over 2 grams lithium)

Forbidden Forbidden
Lithium-Ion Battery Installed in a Device
(up to 8 grams lithium equivalent content)
Permitted 1
Recommended 1
Spare Lithium-Ion Battery (Not Installed in a Device)
(up to 8 grams lithium equivalent content)

Forbidden
Permitted in carry-on baggage 2
“Special Case”
Up to 2 Lithium-Ion Batteries, Spare or Installed
(between 8 and 25 grams aggregate lithium equivalent content)
Spare Batteries: Forbidden!
Installed in Devices: Permitted 1
Spare Batteries: Permitted 2
Installed in Devices: Permitted 1
 
 
1. Although you may carry some devices and installed batteries in checked baggage, carrying them in carry-on baggage, when practicable, is preferred. Whether in checked or carry-on baggage, ensure that devices remain switched off, either by built-in switch/trigger locks, by taping the activation switch in the “off” position, or by other appropriate measures.
 
 
2. Be sure to take protective measures to prevent against short-circuits. See the spare battery tips and how-to pages.