A surprisingly open discussion of what it takes to make the Sanyo
Eneloop LSD (low self discharge )cells.
Note that the new version Eneloop cells have  substantially superior
specifications to the older version.

5 pages. Not excessively technical but addresses key areas.

         http://www.eneloop.info/fileadmin/EDITORS/ENELOOP/ARTICLES/Teraoka=
_Article_EN.pdf

Development of Low Self-discharge
Nickel-metal Hydride Battery
Hirohito Teraoka
Technical Marketing Department
SANYO Energy Twicell Co., Ltd.
307-2, Koyagimachi, Takasaki-City
Gumma, 370-0071 Japan


__________________________

Old & new Eneloop cells have a higher terminal voltage than standard
NimH cells under any given conditions.
Overall combination of low impedance and higher voltages tends to give
substantially superior performance to std NimH or Alkaline cells.

Note that the new version Eneloop cells have  substantially superior
specifications to the older version.

Charging cycles up from 1000 to 1500
Now retains 75% capacity for 3 years (!)

Lower temperature limit bow -20C rather than -10C.
Note that the cells are substantially affected by temperatures of -10C
and below but that at 0 C they have very close to full capacity.

Old cells part numbers include 3UTG on AA and 4UTG on AAA.
New cells part numbers include  3UTGA on AA and 4UTGA on AAA.

New models also have a stylised 3 pointed crown logo on them.

____

Performance details:

      http://www.eneloop.info/home/performance-details.html

Capacity / voltage curves -
http://www.eneloop.info/home/performance-details/capacity.html

http://www.eneloop.info/home/performance-details/voltage.html

Low & high temperature performance -
http://www.eneloop.info/home/performance-details/low-temperature.html

User guide. Low tech. Some value:
http://www.eneloop.info/fileadmin/EDITORS/ENELOOP/PICTURES/OTHER_PICTURES/h=
andbook.pdf

Manuals and catalogs:
http://www.eneloop.info/fileadmin/EDITORS/ENELOOP/PICTURES/OTHER_PICTURES/h=
andbook.pdf

Sample datasheet - HR-3UTGA  AA new style.
         http://www.eneloop.info/fileadmin/EDITORS/ENELOOP/DATA_SHEETS/HR-3=
UTGA_data_sheet.pdf
Note storage limits wrt temperature and time.


_________________

Eneloop XX
2500 mAh typical
2400 mAh minimum
75% at 1 year.
500 cycles.
--=20
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