You may have heard about temperature compensation as it relates to battery charging. In this article, we cover the theory behind the need for battery charging temperature compensation and the real world benefits of this feature for professionals and consumers alike.
First, The Theory.
The ideal storage and charging temperature range for a lead acid battery is 70˚-77˚F. The battery charging process is, at its essence, a managed chemical reaction (pushing or forcing current onto the battery’s positive plates). All chemical reactions are impacted by the temperature in which they take place. In the ideal temperature range, the electrons flow at a specific (normal) rate. In higher temperatures, the electrons flow more quickly and in colder temperatures, the electrons flow more slowly.
The primarily goal of the charging process, bringing the battery to full charge, is really a matter of getting the battery to reach a target voltage and raising the specific gravity of each cell to a precise level. But these targets vary depending on the type of battery that’s being charged, e.g. flooded, AGM, Gel Cell, etc. So, smart chargers that are truly optimized to charge the variety of battery types found in today’s vehicle will have different charging targets based on the type of battery indicated during the charging set-up.
But, as we have seen, temperature impacts the way a battery receives charging energy. As a result, the target voltages for each of the various battery types must be adjusted according to the temperature of the battery. In temperatures warmer than the ideal range, target voltages must be adjusted downward, while in temperatures colder than the ideal range, target voltages must be adjusted upward.
The Real World Impact
The easiest way to illustrate the benefits of temperature compensation is to talk about what charging looks like without it. Without temperature compensation, every battery of a specific type (AGM, for example) will be charged using the same target voltage. This is fine when the battery is being charged in an indoor environment around 72˚F, but becomes an issue if charging is being done in warmer or colder environments. In those cases, the common target voltage for that AGM battery will either be too high (warmer environments) or too low (colder environments). This will result in over- or under-charging the battery.
On traditional flooded batteries, occasional exposure to under- or over-charging may have limited negative impact, depending on how severe the miss is. The same cannot be said for newer battery types, such as AGM and Gel Cell types. Manufacturers of these batteries warn of the dangers from inaccurate charging, particularly over-charging, which results in excessive heat buildup and chemical degradation of the battery. These, in turn, can shorten battery life. In addition, repeated exposure to over- or under-charging, such as in extended storage charging for seasonal use vehicles or in collision repair applications, will compound the impact of inaccurate charging.
Temperature compensation is a key aspect of delivering a beneficial charge and a fundamental feature of a quality “smart” charger. PRO-LOGIX Intelligent Battery Charger/Maintainers, such as Model PL2320, incorporate numerous features that make easy work of delivering a proper charge every time. Fully automatic operation, the ability to properly charge all lead acid battery types, temperature compensation, battery reconditioning capability, an enhanced maintenance routine for ideal long term charging, polarity protection, battery fault detection… PRO-LOGIX battery chargers from SOLAR bring unsurpassed speed, safety and performance to battery service applications.