February 23, 2010

Cheap Batteries Aren't Worth The Cost

If I'm browsing through the battery aisle at the local grocery store for some AA' then I might find the following options:

Energizer Lithium 4 pack for $10.99
Duracell alkaline 'ultra' 8 pack for $5.99
Store brand 8 pack for $4.79

The lithium batteries claim that they are super powered and will last a long long time.   But they cost about 2 times as much for half the batteries.  I get sticker shock if something is multiples the price of an alternative.  Lets look at those prices on a per battery unit cost:

Energizer lithium = $10.99 / 4 = $2.75ea
Duracell 'ultra' =  $5.99 / 8 = $0.75 ea
Store brand  = $4.79 / 8 = $0.60 ea.

My frugal mindset would make me automatically pick those store brand batteries.   But you should be aware that batteries are not all created equal.    Those claims by Energizer that their lithium batteries are super powered and will last extra long are actually based on facts.   On the other hand the cheap store brand batteries may be of inferior quality and may not last nearly as long.

Consumer Reports tested AA batteries and found significant differences.    There is also a video clip of the Consumer Reports study. Consumer Reports found that a store brand CVS battery only lasted 92 pictures on a digital camera while a standard Panasonic alkaline batteries lasted over 2 times as long.   The lithium batteries lasted even longer and they got 678 pictures from the Energizer ultimate batteries.   The high end lithium batteries lasted about 7 times as long as the cheap batteries.

If you look at the cost of the battery per life then the most expensive per battery is actually the best buy:

Energizer lithium = $2.75 battery / 678 pictures = $0.00405 / picture
Standard = $0.75 ea / 184 picts = $0.00407 / pict
Store brand = $0.60 ea / 92 picts = $0.00652 / pict

So due to the low life of the store brand batteries they end up being more expensive.   If I had bought the store brand batteries in the name of frugality thinking I was getting a good deal I might have ended up actually spending 50% more over all.

Rechargeables the best deal

Better yet for situations where you frequently use a lot of power and go through a lot of batteries then getting rechargeable batteries would be the most cost effective solution.

Consumer Reports also found that the Sanyo Eneloop brand batteries were the highest performing rechargeable.  They got 400 pictures from the Eneloop and Sanyo claims you can recharge them up to 1000 times.    A Sanyo Eneloop 4 Pack AA NiMH Pre-Charged Rechargable Batteries w/ Charger costs $16.46 at Amazon.   That is $4.11 per battery.   Even if you were only able to recharge them 100 times (just 10% of Sanyo's max claim) that would give you 40,000 pictures for $4.11.  

You'd also have to pay the electricity cost to recharge the batteries.  Trent at The Simple Dollar looked at the costs of recheargeable batteries a while back and included the cost of the electricity to charge the batteries.   His calculations figured that it cost 0.02 kiloWatt hr to charge a single AA battery.   At $0.10 per kWh that is a cost of $0.002 per charge.   So 100 recharges would cost you an extra $0.20 in electricity. 

Comparing batteries on cost / picture
Energizer lithium = $2.75 battery / 678 pictures = $0.00405 / picture
Standard = $0.75 ea / 184 picts = $0.00407 / pict
Store brand = $0.60 ea / 92 picts = $0.00652 / pict
Sanyo Eneloop rechargeable = $4.31 / 40,000 picts = $0.000107 /pict

Those very small $ values are hard to compare so lets look at it in the sense of pictures per $1 spent on battery:

Energizer lithium = $0.00405 / picture = 246 picts
Standard = $0.00407 / pict = 245 picts
Store brand = $0.00652 / pict = 153 picts
Sanyo Eneloop rechargeable = $0.000102 /pict = 9,280 pictures

The rechargable Eneloop battery is the clear winner. 

Blog Widget by LinkWithin