EN Series: Endurance

Suitable for all standby applications including Telecommunications, UPS, Emergency Lighting. Endurance range Batteries from Yuasa are the engineer's choice for even the most critical DC standby application.

Features include:
- Long life in standby (10 year design life)
- Unique mix and match parallel assembly allows extensive variations to network capacity
- Electrolyte Suspension. A.G.M. technology assures no free electrolyte to spill or worry about
- High gas recombination efficiency. Eliminates the need for forced ventilation and separate battery rooms
- Case Material Oxygen Index 30
- Fully compliant with BS6290-4 and IEC896-2

NP Series: VRLA

Yuasa NP batteries, having excellent deep discharge recovery characteristics coupled with long life on float standby, are ideal for numerous applications in both cyclic and standby modes.

NPL Series: VRLA

NPL Valve Regulated Lead-Acid Batteries (VRLA)

The NPL range is an enhanced NP design resulting in a longer service life (7-l0yrs). All other attributes and operational characteristics are the same, thereby maintaining the benefit of a common mechanical and electrical design for users of both products.

Features
- Yuasa VRLA batteries can be used in any orientation excluding continuous use inverted
- Standard case material is flame retardant to (UL94) HBO
- FR option case material is flame retardant to VO (UL94) (oxygen index 30)
- NPL batteries are manufactured within the ISO9000 Quality Assurance Standard
- FR option NPLs comply with BS6290 Part 4 (1997)

Ni Cad: Emergency Lighting Battery Packs

- A very high grade non-woven polypropylene material is used as the separator. This component exhibits superb chemical and mechanical stability characteristics at elevated temperatures.

- The sintered positive electrode is designed and manufactured to minimise volume changes during oxidation.

- A modified electrolyte solution increases stability of the electro-chemical and mechanical behaviour of the cell at elevated temperatures.

GAS PRODUCTION IN SEALED LEAD ACID BATTERIES

A. Hydrogen is produced within lead-acid batteries when charging takes to the electrolysis of water.
The rate of hydrogen production may be calculated using the formula,

Hydrogen = 0.456 x I litres per hour per cell where I is the charging Amps.

The fraction of hydrogen produced from electrolysis that is actually generated for emission will depend on the recombination efficiency of the cell, and may be calculated using the formula,

H = 0.456 x I x (1-z) litres/hour/cell where z is the recombination efficiency of the cell.

B. Example calculation:

i. If the recombination efficiency of the cell is 100% then any hydrogen evolved will be at a very slow rate, from the corrosion of internal battery components. This type of hydrogen evolution will be very dependent on the mode of use, but for continuous float charge an approximate figure is:

100 millilitres/Ampere hour capacity/cell/Annum.

E.g. NP 24-12 would produce approximately 14.4 litres per year.

ii. If the recombination efficiency is only 85% and the overcharge current is 10 Amps then the volume of hydrogen will be 0.684 litres/hour/cell.

C. Recombination efficiency of Yuasa Batteries. NP SERIES - it can be seen that NP batteries have practically 100% recombination efficiency of the charging current is below 0.01 CA. As the maximum overcharge current in normal float conditions is less than 0.004C it can be seen that condition B i. applies for NP batteries in normal float service.

NB. In the event of malfunction of the charging systems to produce overcharge the rate of hydrogen production may be calculated as in B ii. above.

The low maintenance and valve-regulated constructions combine with heavy-duty plates and unique separator systems to make NPC service twice as long as conventional counterparts

Features
1. Double Cycle Life
NPC operates 500 charge/discharge cycles or twice as many cycles as conventional cycle use batteries at 75% D.O.D. (depth of discharge).
2.Valve-Regulatd and Maintenance-Free
Battery electrolyte retained solidly in the separator and innovative gas recombination system allows minimum gas emittance freeing the user from maintenance.
3.Durability For Deep Discharge Use
Yuassa's state-of-the-art plate barrier prevention and the unique separator system help endure deep discharge use thus considerably prolonging battery's service life.
4.Minimal-Self-Discharge
Cyclic use batteries tend to be left discharged after usage causing plate corrosion leading to shortened life. Self-discharge rate of NCP is a small as only 0.1% a day at 20% and thus extends the storage period allowed.