Tubular battery is a type of lead acid battery
in which the positive electrode is not a grid, but a comb like lead
skeleton that holds the positive material with the help of tubular
bags. The structure looks like a series of tubes kept side by side
along the length of the electrode, hence the name “tubular”. Tubular
batteries are used in applications like home power backup, electric
propulsion of vehicles, solar equipment etc. Tubular batteries are
“deep discharge” kind of batteries i.e. You will get a small amount
of current (5–10Amps) for a very long period of time (12–24 hours).
Tubular batteries cannot produce burst of current because the
electrodes are thicker than the ones in a flat plate model and hence
produce a low surface area. That’s why they cannot be used in
applications where a huge amount of current is needed for a very
short length of time (like starting your car in the morning).
Tubular batteries are known to last twice as long as a normal flat
plate battery because the positive active material does not shed off
due to protection offered by the tubes. Positive material shedding
is the primary reason for failure of lead batteries. Typical life
ranges from 4 to 8 years.