Battery Longjevity at DVinfo.net

Glynn Morgan · May 5th, 2009, 12:41 PM

How does one store their batteries? My battery manual says a 90% charge is optimum storage for a night, and 50% charge for long periods of time. Does this accurately describe the charge requirements to save the life of your battery? or does it sound phooey?

I am using an Sony XDCAM EX, but I suppose it is a lithium ion like most batteries.

Ervin Farkas · May 6th, 2009, 09:45 AM

Storing a Li-ion battery at the correct temperature and charge makes all the difference in maintaining its storage capacity. The following table shows the amount of permanent capacity loss that will occur after storage at a given charge level and temperature.

Permanent Capacity Loss versus Storage Conditions Storage Temperature
40% Charge 100% Charge
0 °C (32 °F) 2% loss after 1 year 6% loss after 1 year
25 °C (77 °F) 4% loss after 1 year 20% loss after 1 year
40 °C (104 °F) 15% loss after 1 year 35% loss after 1 year
60 °C (140 °F) 25% loss after 1 year 80% loss after 6 months
Source: BatteryUniversity.com[28]

It is significantly beneficial to avoid storing a lithium-ion battery at full charge. A Li-ion battery stored at 40% charge will last many times longer than one stored at 100% charge, particularly at higher temperatures.[28]

If a Li-ion battery is stored with too low a charge, there is a risk of allowing the charge to drop below the battery's low-voltage threshold, resulting in an unrecoverable dead battery. Once the charge has dropped to this level, recharging it can be dangerous. Some batteries therefore feature an internal safety circuit which will prevent charging in this state, and the battery will be for all practical purposes dead.[citation needed]

In circumstances where a second Li-ion battery is available for a given device, it is recommended that the unused battery be discharged to 40% and placed in the refrigerator to prolong its shelf life. While the battery can be used or charged immediately, some Li-ion batteries will provide more energy when brought to room temperature.

From Wikipedia

Bill Ward · May 7th, 2009, 12:17 PM

I think a visit or an e-mail to your battery manufacturer might be a more accurate source than a general info LI-ion page on Wikipedia.

For example, here is the IDX PDF on how to store batteries:

http://www.idxtek.com/pdf/tech_info/T-005.pdf

May 5th, 2009, 12:41 PM	#1
Glynn Morgan Regular Crew Join Date: Feb 2009 Location: Australia Posts: 119	Battery Longjevity How does one store their batteries? My battery manual says a 90% charge is optimum storage for a night, and 50% charge for long periods of time. Does this accurately describe the charge requirements to save the life of your battery? or does it sound phooey? I am using an Sony XDCAM EX, but I suppose it is a lithium ion like most batteries.

May 6th, 2009, 09:45 AM	#2
Ervin Farkas Inner Circle Join Date: Aug 2005 Location: Atlanta/USA Posts: 2,515	Storage temperature and charge Storing a Li-ion battery at the correct temperature and charge makes all the difference in maintaining its storage capacity. The following table shows the amount of permanent capacity loss that will occur after storage at a given charge level and temperature. Permanent Capacity Loss versus Storage Conditions Storage Temperature 40% Charge 100% Charge 0 °C (32 °F) 2% loss after 1 year 6% loss after 1 year 25 °C (77 °F) 4% loss after 1 year 20% loss after 1 year 40 °C (104 °F) 15% loss after 1 year 35% loss after 1 year 60 °C (140 °F) 25% loss after 1 year 80% loss after 6 months Source: BatteryUniversity.com[28] It is significantly beneficial to avoid storing a lithium-ion battery at full charge. A Li-ion battery stored at 40% charge will last many times longer than one stored at 100% charge, particularly at higher temperatures.[28] If a Li-ion battery is stored with too low a charge, there is a risk of allowing the charge to drop below the battery's low-voltage threshold, resulting in an unrecoverable dead battery. Once the charge has dropped to this level, recharging it can be dangerous. Some batteries therefore feature an internal safety circuit which will prevent charging in this state, and the battery will be for all practical purposes dead.[citation needed] In circumstances where a second Li-ion battery is available for a given device, it is recommended that the unused battery be discharged to 40% and placed in the refrigerator to prolong its shelf life. While the battery can be used or charged immediately, some Li-ion batteries will provide more energy when brought to room temperature. From Wikipedia __________________ Ervin Farkas www.AtlantaLegalVideo.com

May 7th, 2009, 12:17 PM	#3
Bill Ward Major Player Join Date: Jul 2005 Posts: 580	I think a visit or an e-mail to your battery manufacturer might be a more accurate source than a general info LI-ion page on Wikipedia. For example, here is the IDX PDF on how to store batteries: http://www.idxtek.com/pdf/tech_info/T-005.pdf