Lead-acid battery technologies
An innovative new lead-acid battery using a technology known as Thin Plate Pure Lead (TPPL) offers OEMs and end users a practical and cost-effective alternative to both conventional lead-acid and Li-ion batteries. TPPL technology overcomes many of the disadvantages of lead-acid batteries and enables users to achieve the productivity, economy and safety that are essential in today's competitive market environment.

There are four basic types of lead-acid batteries: Wet lead-acid batteries (lead-antimony), valve-regulated lead-acid (VRLA) gel batteries (lead-calcium), VRLA non-woven (AGM) batteries (lead-calcium) and pure lead batteries (TPPL) (pure lead - VRLA - AGM).

Lead-acid wet batteries offer a good cycle life, but have certain disadvantages due to their design. For example, the charging process is not optimal, as these batteries typically require charging times of eight to twelve hours and an overcharge of around ten to 20 percent to create a sufficient acid mixture and minimize stratification. In addition, water must be topped up regularly. Fast charging is possible in principle, but requires special chargers equipped for battery and charging algorithms.

Commercially available VRLA batteries, both gel and AGM batteries, offer an improvement here. However, they have a limited charging capacity and therefore require a longer charging time of eight to ten hours. With current gel batteries, fast charging with high-current charging programs is difficult.

Advantages of TPPL technology
The pure lead battery is a further development compared to other lead-acid batteries, which is based on two core concepts: Thin plates and pure lead.

Thin plates: The positive and negative electrodes of a TPPL battery are only one millimeter thin, compared to nine millimeters in conventional lead-acid batteries. This means that significantly more electrodes can be accommodated in the same space, which increases the capacity and boosts the power density. The space required for the same capacity can be reduced by around 30 percent compared to an AGM battery.

Pure lead: AGM VRLA batteries use a lead-calcium alloy for the positive and negative plates. TPPL batteries use high-purity lead in combination with high-purity sulphuric acid. This makes the chemical behavior of the batteries much more stable, resulting in advantages in terms of charging properties and service life. In addition, the plates are far less susceptible to corrosion due to the grain structure of the pure lead.

Like the previous VRLA products, the TPPL batteries are also encapsulated types with minimal outgassing, which do not require topping up with water. Their design results in a very low internal impedance of the batteries and enables both a high discharge rate and fast, efficient charge absorption. This makes partial charging, also known as intermediate charging, possible. Operators therefore have the opportunity to recharge the discharged batteries with high currents in a short time during shift changes or lunch breaks. At the weekend, the battery can then undergo a full charge followed by an equalization charge to restore the maximum state of charge.

The batteries can be charged in the range from 0.4 K5 to 0.7 K5, two to four times the normal charging rates of AGM and gel batteries. Fast charging algorithms for cyclic applications are available for fast and safe charging. Partial charging is possible without negative memory effect. MartinWalsh/as