Page 528 - Battery Reference Book

50/16 Lead-acid (secondary) batteries
Table 50.13 Batteries for marine applications
Basic construction All-purpose marine Engine starting battery (R series) Buoy lighting battery MW 17
battery (M series) and MB 19

Positive plates Tubular plates Flat pasted plates Flat pasted plates
Negative plates Flat pasted plates Flat pasted plates Flat pasted plates
Separators Microporous sleeves Microporous sheet and glass Microporous sheet and glass
wool mat wool mat
Cell boxes Resin rubber Resin rubber Resin rubber
Cell lids Resin rubber Resin rubber Resin rubber
Collectors Bolted inter-unit Bolted Wing nuts
Burned inter-cell
Container Wood tray holding 2-8 Either resin rubber monoblocs Either metal containers or
cells or wood trays wood trays

Table 50.14 Range of Powersafe low-maintenance lead-acid standby batteries available from Chloride Power Storage
Cell Voltage Capacity at Maximum dimensions (mm) Weight
tyge (VI 3 h rate (kg)
(20"C/1.8 V p.c.) Height Length Width
VA17 2 48 208 106 117.5 5.2
2VB 1 1 4 80 235 206 210 15.6
3VB9 6 64 235 206 210 18.8
3VB 11 6 80 235 206 210 22.0
VC13 2 110 296 121 167.5 13.5
2VB13 4 90 224.5 204 204 17.6
2VB 15 4 105 224.5 204 204 19.8
2VB17 4 120 224.5 204 204 22.0
VB26 2 180 224.5 204 204 17.6
VB30 2 210 224.5 204 204 19.8
VB34 2 240 224.5 204 204 22.0

Plant6 cells. As with Plant6 cells, the rate of loss same commercial life as the positives, thus giving max-
is dependent on ambient temperature and it is there- imum economy in the life of the cell. Microporous
fore recommended that Powersafe batteries, which are envelopes surround each negative plate to give high
delivered in fully charged condition, be stored at as porosity and low electrical resistance, and allow good
low a temperature as possible and given a freshening circulation of the electrolyte. These combine to give
charge every 6 months. efficient internal electrochemical performance.
The product range is listed in Table 50.14. Capacities up to 2152 Ah are available in this range
(Table 50.15). Batteries are also available in moulded
Tubular plate types monobloc containers with capacities up to 250 Ah.
Originally designed for electric road vehicles, the tubu-
lar plate cell can be used for a wide variety of standby 50.2.2 Standby power (stationary) batteries
power applications. This construction gives a very high
electrical output per unit volume. Because the tubu- Most of the major manufacturers of lead-acid batteries
lar plate design is compact it can be used particularly produce a range of these batteries. A typical range is
where space limitations are important. It will also stand that supplied by Varta. The Varta bloc type range is
up to vibration on work where movement of the equip- available in a wide range of capacities and is claimed
ment is involved, or where vibration occurs near the to be maintenance-free for 3 years. These batteries can
equipment. be used both for short-term operation, with bridging
The tubular plate construction is built up with anti- periods in the minutes ranges, and for long-term loads
monial lead spines held firmly in place by a rugged with battery bridging periods of the order of hours.
frame. The active material is held in firm contact The Varta range is available in translucent plastic
with the spines by terylene tubes, minimizing shed- containers as 6V modules with capacities from 12.5
ding of the active material and prolonging battery life. to 150 Ah, as 4 V modules with 175 and 200 Ah, and
The positive plates are matched by perfectly balanced as single cells with capacities from 250 to 2000Ah
pasted negative plates. They are designed to give the (Table 50.16 and Figure 50.5).