Everything you need to know about traction batteries
The battery is an indispensable “gadget” at any modern facility. Power sources with a “chemical filling” began to be produced back in 1800, when A. Volta was able to obtain a continuous voltage type by experiment.
In systems of autonomous, standby power sources of both large industrial complexes, and individual electrical appliances, as well as electric vehicles, an accumulator is indispensable. The most popular type of battery is lead-acid batteries.
Battery Specifications
The key parameters of the battery that determine its quality are:
- Voltage, V;
- Capacity, Ah;
- Permissible discharge depth,%;
- Period of service, years;
- Range of working temperatures, ° С;
- Self-discharge,%;
- Charge current, A;
- Dimensions, mm;
- Weight, kg.
The characteristics indicated by the manufacturer are assumed for the standard temperature range (20 – 25 ° C) and are somewhat reduced in actual use conditions. We will talk about each parameter separately.
Voltage level
The main parameter that affects the choice of the unit. The most common options are with voltage indices of 1.2, 2.4, 6, 12 V. To obtain a battery with a high voltage, several 12-volt batteries are used and connected in series.
The degree of charging and wear of unattended batteries is evaluated after measuring the voltage level in a state disconnected from charging and inactivity. Normally, this parameter is 13-13.2 V.
Capacity
This is the amount of energy that the battery can save. Range: from 0.6 to 4000 Ah. In simple terms, a 200 Ah battery guarantees a load of 2A for 100 hours.
With an increase in the current consumption indicator, as well as during operation, the battery capacity gradually decreases: this should be taken into account.
Marking “C” with a specific numerical value indicates the battery capacity when discharged in a given period of time (C1, C5, etc.). C10 is an accepted standard for 10-hour battery capacity.
Sometimes battery manufacturers write capacitance at C20. This is done to artificially increase the rate.
Remember that with heavy use of the battery and deep discharge, the plates tend to wear out and the battery may break. Therefore, it is important to provide for reserve capacities.
Permissible discharge depth
This characteristic, divided into permissible and recommended, is different for different types of batteries.
Battery Type | Permissible discharge,% | Recommended discharge,% |
VRLA | 70 | 40 |
AGM VRLA | 80 | 50 |
GEL VRLA | 90 | 50 |
OPZV | 90 | 60 |
OPZS | 90 | 60 |
Life time
The level of battery discharge is equal to the intensity of operation when assessing the impact on the service life. If you discharge the battery 100% several times to a voltage of 9 V, then even the most modern model can be malfunctioned. Those. Do not allow discharge below the recommended value.
Each battery has its own “viability”, which largely depends on the operating mode and discharge characteristics. The service life indicated by the manufacturer is conditional, since it assumes the ideal operating mode of the battery. The service life is affected by environmental conditions (high temperatures are undesirable) and completed charge / discharge cycles.
Battery type | Cyclic resource at discharge depth | Service life, years | |||
25% | 50% | 75% | 100% | ||
VRLA | 700 – 1000 | 350 – 500 | 230 – 400 | 150 – 300 | 3 – 5 |
AGM VRLA | 800 – 2100 | 500 – 1200 | 300 – 800 | 200 – 600 | 5 – 15 |
GEL VRLA | 2500 – 3000 | 1200 – 1750 | 800 – 1000 | 600 – 800 | 10 – 15 |
OPzV | 2500 – 3000 | 1200 – 1750 | 800 – 1000 | 600 – 800 | 10 – 15 |
OPzS | 5000 – 6000 | 3000 – 3500 | 1500 – 1750 | 1000 – 1200 | 20 – 25 |
Self discharge
The parameter characterizes the degree of spontaneous drop in capacity when idle after 100% charge. It is indicated as a percentage for a given period of time.
For example, take a 100 Ah AGM VRLA battery, infected and not in use for a month. The average percentage of self-discharge is 1.5%, which means that the battery capacity in 30 days will be about 98.5 Ah. With an increase in external temperatures, the figure will also increase.
Charge current
The current strength of the charged battery also depends on the capacity. Lead-acid batteries are charged with 10-30% current from the nominally installed capacity. You can use and charge less power.
It is unacceptable to charge the batteries with high current, as this causes serious disturbances and reduces the operational life.
Weight, dimensions
These indicators are affected by capacity. There are also the so-called generally accepted sizes of small batteries up to 250 Ah. The height of the product should be evaluated with and without terminals.
Weight refers to an additional quality characteristic: the heavier the battery, the more lead it has, the higher the cyclic life and the longer the service life.
When choosing a battery, we recommend that you consult a specialist online store who will offer the best model for solving individual problems!