Photo voltaic and materials dealing with tools are normally powered by deep cycle batteries. It’s a complicated expertise that’s evolving quickly.
About Deep-Cycle Batteries
Deep-cycle batteries (Take 12 volt deep cycle battery for instance ) are reusable chemical vitality storage units designed to offer regular energy over an prolonged time frame, and to be absolutely discharged and recharged a number of instances. Though they’re shut cousins of the unusual automobile battery, they’ve completely different traits:
Automotive batteries are designed to ship a short burst of intense energy after which return to charging.
This distinction is vital, as a result of utilizing a automobile battery in tools designed for deep cycle batteries–or vice versa–can have fairly pricey penalties.
There are a number of sorts of deep cycle batteries, with completely different chemical compositions and inner constructions.
Flooded lead-acid batteries
These batteries, also called moist cells, are based mostly on lead-acid chemistry found in 1859 by Gaston Planté, and are additionally the oldest type of rechargeable battery. They comprise electrodes (lead plates) immersed in an electrolyte (a mix of distilled water and sulfuric acid), in an unsealed casing. Though low-cost and easy, lead-acid batteries are more and more being deserted in favor of extra fashionable sorts.
Benefits :
– Low-cost
– Excessive surge present
– Easy design permits for straightforward troubleshooting and restore
Disadvantages:
– Requires common upkeep and topping up with distilled water.
– The unsealed case should be stored upright, in any other case the electrolyte will leak.
– Very heavy in comparison with the quantity of saved vitality (low vitality density).
– Emits explosive hydrogen throughout charging, which requires good air flow.
– Should be shipped as harmful items
The necessity to safely vent hydrogen whereas charging lead-acid batteries is the first purpose for the vents and grills discovered on older battery-powered tools.
Sealed AGM batteries
Sealed Absorbent Glass Mat AGM batteries use the identical chemistry as flooded lead-acid batteries, however as a substitute of a pool of acidic water, the electrolyte is made up of acid-soaked fiberglass mats sulfuric. The housing is totally waterproof apart from a strain aid valve. This ends in a compact, maintenance-free battery preferrred for the army functions for which it was initially developed.
Benefits :
– Lighter and smaller than flooded lead-acid batteries for a similar capability.
– No common upkeep or refilling is required
– The low inner resistance permits very quick charging, with diminished vitality loss.
– Waterproof case permits batteries for use, saved or transported in any orientation.
– No hydrogen emissions in regular use, lowering air flow necessities.
– Sluggish self-discharge price, appropriate for long-term storage.
– It’s not essential to ship them as harmful items.
– Most typical sort of deep cycle battery
Disadvantages
– Costlier than flooded lead acid batteries
– Charging too shortly or overcharging can injury the battery.
– Comparatively tough to diagnose or restore.
– Very heavy, with low vitality density
Sealed GEL batteries
Sealed GEL batteries are one other sort of lead-acid cell, with a semi-solid “GEL” electrolyte. Like AGM batteries, they’ve a sealed casing, can be utilized in any orientation with out leaking, and usually don’t launch hydrogen. Nevertheless, they are often broken by improper charging.
Victron vitality makes use of good digital chargers to guard the GEL batteries of its photo voltaic merchandise.
Benefits
Batteries small, sturdy, extraordinarily dependable, requiring no common upkeep.
The sealed case permits the batteries for use, saved or transported in any orientation.
Can stand up to very deep discharges with out being broken.
No hydrogen emissions in regular use, lowering air flow necessities.
Very sluggish self-discharge price, round 3% per 30 days, appropriate for long-term storage.
It doesn’t have to be shipped as harmful items.
Extra immune to shocks, vibrations and temperature variations than different sorts of lead-acid batteries.
Disadvantages
Sometimes 30% greater value than equal lead acid batteries.
May be completely broken by improper charging
Comparatively tough to diagnose or restore.
Very heavy, with low vitality density
Sealed GEL batteries are the most costly sort of lead acid battery, and usually essentially the most sturdy. Solaire merchandise are provided completely with this sort of battery.
Different sorts of deep cycle batteries
Along with these listed above, different deep cycle batteries can be found with completely different inner chemistries. The very best identified is lithium phosphate battery – the brand new light-weight and highly effective batteries utilized in cell telephones and electrical automobiles. Though deep-cycle lithium-ion batteries can be found for industrial use, they’re fairly susceptible to fires and their value is usually not but low sufficient to compete with lead-acid batteries.
Understanding battery traits
Even the most lasting battery will ultimately have to be changed – and since deep cycle batteries are costly, it helps to grasp the alternative ways to price and evaluate them.
Listed below are the 4 commonest indicators:
Amp-hours
The primary quantity most individuals search for is ampere-hours (Ah), which expresses the entire quantity of chemical vitality the battery can retailer and launch as electrical energy. Amp-hours will be understood merely because the period of time the battery will function earlier than needing to be recharged.
A multimeter can be utilized to verify the voltage generated by a battery.
One other vital measurement is voltage (V), which signifies the electromotive pressure – or “energy” – of the present provided by the battery. Like {most electrical} techniques, photo voltaic merchandise are designed to work with a specific voltage and will likely be broken by the next present. It’s important when changing batteries to make sure that the voltage is appropriate.
C-index
The capability of a battery truly varies in keeping with its use, one other helpful indicator is the C index.
Merely put, the C score defines how lengthy a battery must be discharged, with the intention to ship its rated capability. A 10Ah battery with a C score of 1C will ship 10Ah in 1 hour, however much less energy if discharged sooner, and extra energy if discharged slower.
Though the C index refers to time in hours, it’s an inverted unit – a 2C index means half-hour, and a 0.2C index means 5 hours. That is typically simplified by utilizing a division operator to re-invert the unit, so C/2 means 2 hours, and C/20 means 20 hours. Most deep cycle lead acid batteries are designed to discharge their rated capability in 20 hours which will be expressed as 0.05C or C/20.
Battery Life Comparability
Batteries are typically rated by their lifespan, which is the variety of instances they are often discharged and recharged with out shedding greater than 20% of their capability. The commonest reference is the IEC 60896 normal, which is predicated on a repeated deep cycle of 100% discharge/recharge. Though deep cycle batteries usually are not usually used on this method, it’s a good indicator of their doubtless longevity.
Fairly often, equivalent batteries have completely different lifespans, which is helpful when evaluating batteries from completely different producers or when selecting a battery for a specific utility.
These merchandise are provided with sealed GEL batteries, usually 21Ah 12V C/20. They’re extraordinarily sturdy, but when one among them fails, it should be changed with a battery equivalent to that provided by photo voltaic vitality. For those who should use a generic battery, make sure that it’s a sealed GEL battery with the identical amp-hours, voltage, and C-rating as the unique battery. By no means combine outdated and new batteries, or batteries of various sorts.
Battery upkeep
Though sealed lead-acid batteries require little upkeep, their lifespan will be considerably prolonged by following a number of easy guidelines.
Batteries shouldn’t be commonly discharged beneath 20% of their capability, as recharging a deeply discharged battery generates warmth and accelerates sulfation, which damages the electrodes. More and more, computerized circuit breakers are getting used to stop over-discharge.
Saved batteries discharge slowly and have to be recharged sometimes to stop them from absolutely discharging, which is able to trigger sulfation and injury the battery. The sealed GEL batteries utilized by Nrjsolaire in photo voltaic vitality in Senegal and have a really low self-discharge price of round 3% per 30 days, which suggests they are often safely saved for 2 years with out recharging. . Different sorts of batteries have to be charged extra typically.
Lead-acid batteries should be charged correctly. Charging too shortly or overcharging could not solely injury the battery, but additionally trigger acid leakage, quick circuit, hydrogen fireplace or battery case explosion. It’s all the time really helpful to make use of an clever digital floating charger with computerized present and temperature regulation, such because the on-board chargers fitted to the merchandise.
Flooded lead acid batteries require further checks and upkeep, however are now not widespread in industrial tools.
For many fashionable deep-cycle batteries, that’s all there may be to it. Observe these easy guidelines and your battery provides you with a whole lot of cycles and a few years of trouble-free service.
