Latest from the Blog

Battery Open Circuit Voltage Characteristics.

Wednesday, 10th May 2017 Battery Advice

The open circuit voltage of lead acid cells can give us useful information providing it is used correctly.

This article shows the relationship between the open circuit voltage and state of charge of lead-acid cells and how to interpret the values. The values are always considered as that of a single cell and monobloc voltages must be averaged according to the number of cells. This method was developed primarily for VRLA cells where the specific gravity cannot be measured. Measurement of the specific gravity will give a good indication of the state of charge. For measurement of either specific gravity or open circuit voltage, the fully charged and fully discharged specific gravity must be known. Used correctly, the method described in this article will give reasonable results to the state of charge of cells on open circuit.

Continue Reading...

Lead Acid Batteries For Cycling Applications.

Friday, 31st March 2017 Technical

There have been many myths about lead-acid battery cycling.

This article will give the reader a better understanding of the more important aspects of battery cycling and battery choice. Different applications are discussed along with charger requirements and how the number of cycles varies with the depth of discharge. This article looks at applications where the recharge is not regular such as solar and wind charging. Intermittent diesel charging is also discussed.

Continue Reading...

Battery Internal Resistance & Short Circuit Current.

Friday, 16th December 2016 Technical

Battery internal resistance and short circuit current values are available from battery manufacturers. The method used to arrive at the published values varies but when a method recognised by International Standards is used a comparison between products can be considered.

Searching the internet will reveal many papers discussing actual case studies where a battery has been shorted and interesting results have been obtained. With no fuse or battery circuit breaker in the system short circuits may result in fires and catastrophic failure. Alternatively, the protection may work and isolate the battery from the point of failure and the load resulting in loss of power to the equipment which the battery was intended to protect. It therefore follows that the subject of battery short circuit current can have at least two points of view when looked at in practical terms.

Continue Reading...

How To Make A VRLA Battery.

Thursday, 27th October 2016 Technical

This article discusses the manufacturing principals and processes in the manufacture of VRLA batteries. The article discusses the manufacturing processes and how deviations from the ideal can seriously affect the finished product.

The article assumes the reader has a reasonable knowledge of the construction of both AGM and GEL types. The process described here is very much simplified but will give the reader an understanding of the processes involved in manufacturing VRLA batteries.

Continue Reading...

How Should Industrial Batteries Be Stored?

Friday, 2nd September 2016 Battery Advice

This article discusses the effects of storing VRLA AGM & GEL types and also vented Planté, Pasted Plate and Tubular types.

The article covers the effects of time, temperature, humidity and light and also discusses sulphation; lead dendrite growth and corrosion of the internal lead parts as well as corrosion to the pillars and UV aging of the plastic containers. The relationship between open circuit voltage and state of charge is also discussed.

Continue Reading...