Lead-acid battery manufacturers generally guarantee their products for a period after they leave the factory. Thus makes good commercial sense for two reasons. Firstly, they seldom stay in a dealer stockroom long. Secondly, it makes their nationwide warranties easier to administer. If a new lead-acid battery is still in a dealer’s stockroom after say three months, they will recharge it to keep it fresh but this does take away one of its many lives.
Ask the Dealer to Confirm the New Lead-Acid Battery Age

Any reputable battery supplier should volunteer the date their supplier shipped a particular new lead-acid battery. They have to know this for stock control.
Besides, battery manufacturers take care to date-stamp their products carefully. This is the only reliable way to trace an individual product among many millions sold.
How to Confirm the Date of Manufacture of a Used Battery
Most folk are unconcerned about the age of lead-acid batteries in a used car lot. Pretty much the same applies to sealed lead-acid batteries in UPS Battery systems, recreational vehicles, and so on. As long as the battery still does its job, they are likely more interested in the cosmetic appearance of what is for sale. It’s actually quite simple to confirm a battery date.

However there is no standard regarding how battery factories provide this information.
Some manufacturers stamp their date codes on battery terminals, while others engrave the cases. Some provide the information on the label.
Hence, it is a good idea to note the date stamp on the paperwork for a new lead-acid battery, just in case you need it. The codes themselves do not follow a single norm either.
Most manufacturers use an alpha numeric system whereby the letter is the month, and the number is the year. Thus a battery labeled B-7 would have left their works in February 2017. There are exceptions to this rule. You may need to check with the original new lead-acid battery supplier, to be double sure.
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Preview Image: Lead Acid Starter Battery