The Miata Battery - More Choices Than Ever BeforeEvery Miata manufactured and sent to the U.S. since 1989 has been factory equipped with a special battery. I wrote an article for the SAN DIEGO MIATA CLUB NEWS in 1997 that detailed the stock Miata battery and an alternative aftermarket replacement (SDMC News, Volume 2, Number 6). This article is available on the SDMC Web site and on Miata.net in their respective Garage sections. Since that article was written, changes have occurred in the area of batteries for the Miata. The OEM (original equipment) battery is a product of Panasonic. This battery caused confusion early in the sales of the Miata, since it did not require service like a standard car battery. In addition, mechanics who tried to "quick charge" it found out they quickly ruined it. At the same time, Miata owners were finding out this is one great little battery. Usually a car battery will last, on average, 36 months. If you take good care of it, and live in a temperate climate, 48 months might be expected. The Panasonic has a demonstrated average life of 6 years (72 months) and there are continuing reports of original Miata batteries still going strong beyond the 10th year of service. Still, people complained when they had to shell out $130 for a replacement from Mazda. In mid 1998, Mazda quit selling the Panasonic battery as a replacement for the Miata. When you go to a Mazda parts department you now get a standard wet cell (albeit sealed) battery. The price is only around $80, but you will NEVER see 72 months of service from this battery. Mazda claims this change in batteries was due to customer complaints about the original battery. Well, I cannot dispute that, but I believe that economics played a larger role. The Panasonic battery is made in Japan. In order to supply Mazda parts departments in the U.S. with batteries, they need to ship pallets of very heavy, thereby costly, batteries over the ocean. The new replacement is manufactured in the U.S. and is not subject to long ocean voyage transportation costs. That is why every Miata that enters the U.S. still carries a Panasonic battery in the trunk. No sense shipping U.S. made batteries to Japan! Another strike against the new replacement battery from Mazda is one of commitment. The original design of the Miata placed the battery in the trunk for good weight distribution. This helped the handling of the car, as we all know, but it was not a place for a corrosive and possibly explosive item like a car battery. That is why Mazda chose an Absorption Glass Mat (AGM) battery to be placed in the Miata. The AGM is a suspended electrolyte battery that ties up the battery acid in a fine fiberglass mesh and keeps it from spilling in your trunk. If this design was important enough for the factory to install it (and they still do) then why should we accept less for a replacement battery? Well, a lot of enthusiastic Miata owners do not accept less. WestCo has been providing a replacement AGM battery for the Miata since it had a 1.6 liter engine. This battery was cheaper than the Mazda Panasonic battery and still had the virtues of the OEM unit. One small drawback to the WestCo battery was the reversed battery terminals, in relation to the Panasonic battery. By turning the battery around when installing it this was negated, but the battery cables in the Miata trunk were sometimes very short in this arrangement. WestCo changed this in 1999 and the terminals are now in the same orientation as the OEM battery. The cost of the new WestCo battery is $80 and it works just as advertised. I replaced my 7-year-old Panasonic unit with one in November 1999 and it is working just fine. American Battery Corporation has introduced a new player to the Miata replacement battery scene. Their American Eagle battery is an AGM, just like the original Panasonic and the WestCo. In addition, it is slightly smaller in size. This smaller size is a good thing, since the terminals are reversed like the first generation WestCo. Since the battery is slightly smaller, the short cables are less of a problem when making the connections. SDMC member BRIAN GOODWIN has been using one of these batteries for several months in his '94 Miata and likes it very much. The list price for the American Eagle Battery is $80, same as the WestCo. While the reversed terminals might seem to handicap the American Eagle battery, the specifications make up for it.
As you can see, the American Eagle has the highest cranking amps of the three replacement batteries. That, coupled with the discounted price of $59.90 to SAN DIEGO MIATA CLUB members, makes the American Eagle battery worth considering when your Panasonic finally dies of old age. Either the American Eagle or the WestCo are deserving candidates as re-placements for the Panasonic battery in your Miata. Accept nothing less. - ANTHONY WILDEAmerican Battery Corporation 525 West Washington Escondido CA 92025 (760) 746-8010 WestCo Battery Systems Anaheim CA 1-800-214-8040 www.westcobattery.com/miata.htm |