Which solar battery is best suited for my application?

If you want to store power, batteries are still the most efficient solution. However, there is now a very large number of lead and lithium batteries to choose from and it is often difficult to find out which is really suitable for the corresponding application. 

From time to time, customers can use car batteries for their solar systems. This works but at the beginning is an expensive dinner. A Autobatterie is broken after about 50 cycles, that is at similar acquisition costs, the battery is about 10 times faster broken.

If you are looking for a battery for your holiday home, where you spend a few weeks in the summer and are there 5 - 10 times a week, you do not have to read more, the Varta solar batteries are the best choice, good price, proven for years and A long life span you draw.

The following characteristics are relevant for selecting a battery:

•     Nominal capacity of the battery
•     Really available battery capacity / capacity at high discharge currents
•     Calendar life
•     Cycle life of the battery
•     Charge-discharge efficiency of the battery
•     Maximum tipping angle
•     Temperature behavior
•     Rated voltage (minimum maximum voltage)
•     Max. Discharge current, cold start current
•     Deep discharge behavior
•     Environmental risks, fumes
•     Maintenance work
•     guarantee
•     Lifecycle costs
•     mass
•     Waste disposal, recycling
•     Self-discharging

Applications of batteries

Solar systems for holiday homes
We recommend the normal solar batteries for normal private houses. For professional use, block batteries are the right choice

Campers, police, fire service, work vehicles
Two batteries are normally installed in vehicles. A normal starter battery and a comfort battery, which are coupled via connecting relays during charging. As a comfort battery, you can use a normal solar battery. If the battery is in the interior and no fumes are allowed, we recommend gel batteries. If the weight is a bigger problem, we recommend lithium batteries which can be used with half the amperes (Ah) and are about 3 - 10 times lighter.

Sailing ships
On sailing ships you have to choose a battery that can not leak when you are sloping. In normal cases we recommend gel batteries. If a diesel engine has to be started, an AGM battery is the right choice. If the weight is a bigger problem, we recommend lithium batteries which can be used with half of the amperes (Ah) and are about 3 times lighter.

Telekom
For telecom and similar applications, we recommend the Varta Freedom battery which is 100% maintenance-free and does the service for well over 10 years. For larger installations and if an even longer operating time is required, OPZS lead gel block batteries are the right choice. They last up to 20 years. For even stiffer uses, we use lithium memory.

Aircraft
Only lithium is suitable for electrically powered airplanes. If you want to get the maximum, we recommend lithium polymer, these batteries have the highest power density of all batteries.

Electricity storage for EFH and commercial
Earlier, lead block batteries were used here, but this time is over and only lithium batteries are used which are now available at good prices.

Electric boats
Lithium batteries are normally used in electric ships. If you have to go out in the recreation area only to the port and no longer operating times you can also use AGM batteries.

Alps, SAC huts for professional use
In this professional field we normally use OPzS lead block batteries, if there is no maintenance allowed OPzV gel block batteries which have a lifetime of up to 20 years. If even more power and cycles are required, then lithium home batteries are used.

Car
The usual starter batteries are normally used for cars and motorcycles. We recommend AGM batteries especially for motorcycles, because the self-discharge is much deeper and thus the batteries do not charge over the winter and thus have a much longer life.

Forklifts, wheelchairs
AGM batteries are normally used in small electric vehicles such as forklifts, wheelchairs, golf carts, etc. Lithium batteries are used for professional vehicles with very hard use.

UPS batteries, emergency power
For small battery applications, we recommend AGM batteries. For larger plants, we use OPzS or OPzV lead block batteries.

Characteristics of different battery types

Premium solar battery (Varta)
Nominal capacity of battery storage capacity
Really available battery capacity 30% of the nominal capacity, only in an emergency 100%
Capacity at high discharging currents The capacity decreases strongly at high currents to approx. 50% with one-hour discharge
Calendar lifetime High, 5 to 15 years depending on usage
Cycle life of the battery High with approx. 500 - 1000 cycles
Charging and discharging efficiency of the battery Charging efficiency is approx. 85% of the "Roundtrip" current approx. 75%
Maximum tilting angle Tilting angle 90 ° for a short time, longer up to approx. 40 °
Temperature characteristics Best performance at 20 ° C, higher temperature reduces the service life, low temperature decreases the performance, discharged batteries can freeze, charged freeze only at -50 ° C
Nominal voltage (minimum max. Voltage) 12 V nominal voltage, max. Approx. 14.6 volts, min. Approx. 10 volts
Max. Discharge current, cold start current High max. Discharge current, medium cold start current
Deep discharging behavior Deep discharge is ok, but can not be discharged for a long time, otherwise it will age very quickly
Environmental hazards, vapors Do not dispose of fumes as gas-tight, in an orderly manner
Maintenance No maintenance over the entire service life
Warranty 2 years
Life cycle costs Very low life cycles Costs when used correctly
Weight Very high weight since battery
Disposal, recycling No problem with us or autogarage
Self-discharge Depending on temperature approx. 3% per month

AGM VLRA cordless batteries
Nominal capacity of battery storage capacity
Really available battery capacity 30% of the nominal capacity, only in an emergency 100%
Capacity at high discharge currents The capacity drops sharply at high currents to approx. 65% with one-hour discharge
Calendar life Less than 5 years
Cycle life of the battery High with approx. 1600 cycles at 30% removal
Charging and discharging efficiency of the battery Charging efficiency is approx. 85% of the "Roundtrip" current approx. 75%
Maximum tilting angle Can be operated in any position, 180 °
Temperature characteristics Best performance at 20 ° C, higher temperature reduces the service life, low temperature decreases the performance, discharged batteries can freeze, charged freeze only at -50 ° C
Nominal voltage (minimum max. Voltage) 12 V nominal voltage, max. Approx. 14.2 volts, min. Approx. 10 volts
Max. Discharge current, cold start current High max. Discharge current, high cold start current
Deep discharging behavior Deep discharge is ok, but can not be discharged for a long time, otherwise it will age very quickly
Environmental hazards, vapors Do not dispose of fumes as gas-tight, in an orderly manner
Maintenance No maintenance over the entire service life
Warranty 2 years
Life cycle Costs of life Cycle costs when used correctly
Weight Very high weight since battery
Disposal, recycling No problem with us or autogarage
Self-discharge Less than 2% per month depending on the temperature


GEL VLRA cordless batteries
Nominal capacity of battery storage capacity
Really available battery capacity 30% of the nominal capacity, only in an emergency 100%
Capacity at high discharge currents The capacity drops sharply at high currents to about 60% with one-hour discharge
Calendar Life High at about 10 years
Cycle life of the battery High with approx. 1500 cycles at 30% removal
Charging and discharging efficiency of the battery Charging efficiency is approx. 85% of the "Roundtrip" current approx. 75%
Maximum tilting angle Can be operated in any position, 180 °
Temperature characteristics Best performance at 20 ° C, higher temperature reduces the service life, low temperature decreases the performance, discharged batteries can freeze, charged freeze only at -50 ° C
Nominal voltage (minimum max. Voltage) 12 V nominal voltage, max. Approx. 14.2 volts, min. Approx. 10 volts
Max. Discharge current, cold start current High max. Discharge current, very high cold start current
Deep discharging behavior Deep discharge is ok, but can not be discharged for a long time, otherwise it will age very quickly
Environmental hazards, fumes No fumes since gas-tight, ordered Dispose of
Maintenance No maintenance over the entire service life
Warranty 2 years
Life cycle Costs of life Cycle costs when used correctly
Weight Very high weight since battery
Disposal, recycling No problem with us or autogarage
Self-discharge Smaller than solar battery, depending on the temperature less than 2% per month

OPzV / S Block Stable Batteries
Nominal capacity of battery storage capacity
Really available battery capacity 30% of the nominal capacity, only in an emergency 100%
Capacity at high discharge currents The capacity drops sharply at high currents to approx. 65% with one-hour discharge
Calendar Life High to very high with 10 to 20 years
Cycle life of the battery Very high with approx. 5000 cycles at 30% removal
Charging and discharging efficiency of the battery Charging efficiency is approx. 85% of the "Roundtrip" current approx. 75%
Maximum tilting angle OPzS Operation only recommended in normal position, not tilting, OPzV can be operated in any position
Temperature characteristics Best performance at 20 ° C, higher temperature reduces the service life, low temperature decreases the performance, discharged batteries can freeze, charged freeze only at -50 ° C
Nominal voltage (minimum max. Voltage) 12 V nominal voltage, max. Approx. 14.7 volts, min. Approx. 10 volts
Max. Discharge current, cold start current Very high max. Discharge current, very high cold start current
Deep discharging behavior Deep discharge is ok, but can not be discharged for a long time, otherwise it will age very quickly
Environmental hazards, vapors Do not dispose of fumes as gas-tight, in an orderly manner
Maintenance No maintenance over the entire service life
Warranty 2 years
Life cycle Costs of life Cycle costs when used correctly
Weight Very high weight since battery
Disposal, recycling No problem with us or autogarage
Self-discharge OPzS approx. 3% per month, OPzV approx. 2% per month


Lithium batteries
Nominal capacity of the battery store High capacity with small volume and small weight
Really Available Battery Capacity Approx. 80% of the nominal capacity, only in an emergency 100%
Capacity at high discharging currents The capacity does not decrease with very fast discharge
Calendar Life High to very high with about 10 to 20 years
Cycle life of the battery Very high with approx. 4'000 to 10'000 cycles with 80% removal
Charging and discharging efficiency of the battery Charging efficiency is approx. 97% of the "Roundtrip" current approx. 93%
Maximum tilting angle Depending on type, can be used in principle in any KLage
Temperature characteristics Best performance at 20 ° C, higher and lower temperature reduces the life, below zero degree loading is not recommended
Nominal voltage (minimum max. Voltage) Depending on type 12/24/48/350 Volt, Attention usually slightly different from lead acid battery
Max. Discharge current, cold start current Very high max. Discharge current, very high cold start current
Deep discharging behavior Deep discharge ok, also for longer periods, maximum life with medium voltage between max and min
Environmental hazards, vapors Do not dispose of fumes as gas-tight, in an orderly manner
Maintenance No maintenance over the entire service life
Warranty 2, partial to 10 years manufacturing guarantee
Life cycle costs High costs, with very many cycles very low costs (For hobby use expensive, for professional use very cheap)
Weight Low weight, approx. Three times lighter than lead battery with the same usable energy
Disposal, recycling No problem about disposal site, under construction
Self-discharging Very small approx. 2% month


Lithium polymer batteries
Nominal capacity of the battery store High capacity with small volume and small weight
Really available battery capacity Approx. 80% of the nominal capacity, only in an emergency 100%
Capacity at high discharging currents The capacity does not decrease with very fast discharge
Calendar Life High to very high with about 10 to 20 years
Cycle life of the battery Very high with approx. 4'000 to 10'000 cycles with 80% removal
Charging and discharging efficiency of the battery Charging efficiency is approx. 97% of the "Roundtrip" current approx. 93%
Maximum tilting angle Depending on type, can be used in principle in any KLage
Temperature characteristics Best performance at 20 ° C, higher and lower temperature reduces the life, below zero degree loading is not recommended
Nominal voltage (minimum max. Voltage) Depending on type 12/24/48/350 Volt, Attention usually slightly different from lead acid battery
Max. Discharge current, cold start current Very high max. Discharge current, very high cold start current
Deep discharging behavior Deep discharge ok, also for longer periods, maximum life with medium voltage between max and min
Environmental hazards, vapors Do not dispose of fumes as gas-tight, in an orderly manner
Maintenance No maintenance over the entire service life
Warranty 2, partial to 10 years manufacturing guarantee
Life cycle costs High costs, with very many cycles very low costs (For hobby use expensive, for professional use very cheap)
Weight The lightest battery on the market with the highest energy density, about 10 times lighter than lead acid
Disposal, recycling No problem about disposal site, under construction
Self-discharging Very small approx. 3% month


If the battery capacity is not sufficient in winter, it can make sense to support the system for this period with a generator