Batteries        Last update:  12/18/11
 
"AA" Cells, Brand Comparison:

Test results for several AA primary cells

Conclusion  (Of the batteries tested):
    Members Mark             Best value - most energy per $   (52.7 Minutes/Penny   $0.23/bat) 
    Energizer Lithium       Most energy / battery   (1547 minutes discharge time    $1.67/bat) 

Test Results:

Sorted by best value   (Minutes / Cents)
Make  Minutes Cost /bat Nr in Pkg Minutes/Cent Supplier Part Nr. Date
Members Mark 1,212 $0.23 48 52.7 Sam's 912986 1/10
Thundrbolt 1,188 $0.23 24 51.9 Harbor Freight 92404 12/11
Lexcell 911 $0.20 4 45.6 Jameco 2112444 2/10
Energizer 1,131 $0.40 48 28.3 Sam's 265361 1/10
Werker 1,308 $0.50 8 26.2 Batteries Plus wkaab 12/11
Utilitech 1,096 $0.47 16 23.4 Lowe's 348847 12/11
Duracell Ultra 1,264 $0.87 8 14.5 Lowe's 54534 1/10
Energizer Lithium 1,547 $1.67 4 9.3 Sam's 8/10
Sorted by most energy    (Minutes / battery) 
Make  Minutes Cost /bat Nr in Pkg Minutes/Cent Supplier Part Nr. Date
Energizer Lithium 1,547 $1.67 4 9.3 Sam's 8/10
Werker 1,308 $0.50 8 26.2 Batteries Plus wkaab 12/11
Duracell Ultra 1,264 $0.87 8 14.5 Lowe's 54534 1/10
Members Mark 1,212 $0.23 48 52.7 Sam's 912986 1/10
Thundrbolt 1,188 $0.23 24 51.9 Harbor Freight 92404 12/11
Energizer 1,131 $0.40 48 28.3 Sam's 265361 1/10
Utilitech 1,096 $0.47 16 23.4 Lowe's 348847 12/11
Lexcell 911 $0.20 4 45.6 Jameco 2112444 2/10




Test conditions:

1)    The batteries were connected to a constant load of 12 ohms during the test period.
2)    The total discharge time was recorded until the terminal voltage dropped to 1.08v
3)    Ambient temperature during the test was 70-72 degrees F
4)    All batteries were tested within 5 days of purchase from local stores.

Notes:

These results are thought to be useful comparisons when measured with the same conditions.
However, keep in mind: 
1)   Real life loads are rarely constant resistance, more likely constant current or constant power.
2)   Actual capacity [watt-hours or joules] was not measured.
3)   Also, not addressed, are other factors unique to specific applications such as 
discharge current, ESR (ionic and resistive), battery temp, product cutoff voltage, 
self discharge and other shelf life factors.


Comments:

    1) I did not shop for the best price.  Sales and coupons may change the "best buy" conclusion.
    2) Use Lithium for the greatest energy [and probably longest shelf life], but at much greater cost.
    3) With a constant load, starting current drain is 125mA, end current drain is 90mA
For reference, a 100mA constant load for 1200 minutes = 2000 mA-Hrs
This is about 2.5W-Hrs of energy (for 1.25v average), cost about $0.25 
~1000x more expensive than the grid power  (portable power is expensive)
    4) The Lexcell batteries were provided by Jameco.  They didn't have a use by date.
Their condition is suspect because unloaded initial terminal voltage was 1.40v(#1) and 1.35v(#2)


Conctact information is (HERE) if you have questions or comments.