Tech Zone

Sealed Lead Acid (VRLA) Batteries

SLA (sealed lead acid), also known as VRLA (valve regulated lead acid) batteries are rechargeable with a nominal voltage of 2 volts per cell. Require a float voltage under charge of 2.4 to 2.45 volts per cell (ex. 12 volt battery 14.4 to 14.7 volts). The amount of current the battery can take under charge is largely dependent on the capacity of the cells. Most use a 20 hour discharge to determine their rated capacity. The actual capacity is influenced by the discharge rate and voltage cutoff. Lead Acid Batteries do not develop "memory" in cyclic applications and should be kept fully charged when not in use. Top charge after 6-9 months in storage. They are constructed using an AGM (absorbed glass mat) design or GEL.

AGM batteries have a separator holding the electrolyte made of glass fiber that behaves like a sponge.
Better high rate and low temperature performance.
Faster recombination, lower resistance separator.
Can be installed in any orientation.
Lighter than the GEL construction.

GEL batteries are designed with fine silica particles with a large surface area and are dispersed in the electrolyte.
Accept a lower float voltage than AGM.
Typically provide superior cycle life.

FLOODED lead acid batteries contain a liquid electrolyte.

How to Read SLA Date Codes

YY=Year MM=Month DD=Day

Yuasa

1401173E

YYMMDD Plant/Shift

CSB

130816G11

YYMMDD No relevance to manufacture date

Panasonic

120316A

YYMMDD No relevance to manufacture date

Sonnenschein

P 4013

Plant Week YY

Power Sonic

01 164-U

MM DDY – No relevance to manufacture date

Enersys (Hawker)

14020

YY Day of the year

Enersys (NP series)

1209028B

YYMMDD No relevance to manufacture date

R&D SLA (Part numbers 5389, 5387, 5771, 5918, 5918-A)

 

Year

 

Month

 

A=2006

 

Jan=M

 

B=2007

 

Feb=N

 

C=2008

 

Mar=P

 

D=2009

 

Apr=Q

 

 

E=2010

 

May=R

 

F=2011

 

Jun=S

 

G=2012

 

July=T

 

H=2013

 

Aug=U

 

I=2014

 

Sept=V

 

J=2015

 

Oct=W

 

K=2016

 

Nov=X

 

L=2017

 

Dec=Y

 

NT at the end of the date code has no relevance to manufacture date

 

IVNT = 2014 / September / No relevance to manufacture date

 

Non-rechargeable (Primary) Batteries

Primary batteries are a one time use and need to be replaced when the battery is exhausted.

Rechargeable (Secondary) Batteries

Secondary batteries have reversible chemical reactions so they can be recharged when exhausted and used again.

How to Read NiMH Date Codes

YY=Year MM=Month WW=Week of Year DD=Day

Energy Plus

0117556231

WW YY No relevance to manufacture date