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Batteries for Solar Systems - Renewable Energy Batteries

Batteries are our favorite topic! We have been in the battery business for 51 years. We actually got into the renewable energy business because we were in the battery business. It seems like everybody you talk to who has a bank of batteries is constantly having some sort of crisis with their batteries. Is it the batteries? We think not. Although almost 87% of all batteries die prematurely, it is not the battery’s fault; they die from abuse. Don't despair we will help you choose the best battery for your unique application.

Even a well-intentioned battery owner, who cares for his batteries religiously, can have problems. What are the two principal causes of abuse? Either a poorly designed battery bank or inappropriate charging or both.

The Solar Biz is your best resource to completely avoid the above scenarios. Having designed off-grid systems for a half century we have the technical ability and design experience you absolutely need for your battery purchase.

Batteries may be divided into seven general categories for Renewable Energy. The first two relate to size:

  1. Industrial which are large and heavy, and have long life expectancy.
  2. All the rest, which have a shorter life expectancy and can be moved easily by human power alone.

The next five categories refer to materials and construction:

Wet Cell, GEL, and AGM batteries are all Lead Acid Batteries so the technology is the same. Do remember that you must be able to charge your (lead acid) batteries fully at least once every ten days, so just buying a big battery causes you to have a big charging system, or the batteries will surely fail.

  • Wet Cell Batteries need maintenance and attention; i.e. the never-ending periodic adding of distilled water and keeping the cables clean. They are a good choice economically and they're less expensive than AGM or GEL batteries.
  • Absorbed Glass Mat (AGM) Batteries these are valve-regulated sealed batteries. They are not maintenance free. AGMs do not need the periodic addition of water. Without the fine mist of sulfuric acid, connector cables stay cleaner. Because they are sealed, AGM batteries are not hazardous shipments and they will not freeze even when deeply discharged. AGM batteries cost about a third more than their wet cell counterparts.
  • Gel Cell Batteries Also valve regulated sealed batteries. The sulfuric acid is mixed with silica sand to make a "mud". There are a number of characteristics I don't like about these. They're not kind to a hard charge and you can "cook" them easily. If you do heat them up the "mud" dries out and cracks, just like all mud, and leaves voids next to the grids, thus killing off some of the capacity. These batteries do have folks that love them and swear by them, but they are a small group who know how to maintain them. For most folks, I would recommend buying AGM instead.
  • Salt Water Batteries At this time these are not available. They were the first truly eco-friendly battery, containing no toxic materials at all. All batteries are made up of two dissimilar materials and a liquid, Lead Acid batteries are two types of lead and sulfuric acid. Aquious Ion (salt water) batteries utilize cheap common raw materials which are readily available the design is Manganese and Carbon and the liquid is essentially Salt Water. They're Industrial sized batteries (heavy) with a long lifespan. Little or no maintenance plus the ability to add more capacity later if you need it.
  • Lithium Batteries Lithium batteries are different chemistry than other battery solutions; Some sales people will tell you that they can be discharged to 0% without damage but, what they fail to mention is… that’s when the lights go out! Plus, if you’re charging from solar when the sun comes up your charge controller won’t turn on because it runs off battery voltage, of which you have none.

Today we have two types of lithium batteries on the market: Lithium Ion (Li-Ion), and Lithium Iron Phosphate (LiFePO4) sometimes called Lithium Ferro Phosphate (LFP).

Our biggest concern with Li-Ion batteries comes from thermal runaway, its a dangerous chain reaction, triggered by a source of heat, like overcharging or a house fire, which can lead to a powerful, explosive occurrence. Plus, you can’t put the fire out with water! The Power Wall is this type of lithium battery.

We recommend the LiFePO4 battery technology. LiFePO4 it is a different chemistry than Li-Ion batteries. it is much safer with significantly longer cycle life, lower cost, lower-toxicity and more stability. Victron, Trojan Trillium, RELiON and Simpliphi Lithium are all this type of chemistry.

If you're buying batteries ask us about Our Local Pick-up Options. Available almost everywhere in the 48 States. A small pick up fee may apply. or If pick-up it is not convenient we also have commercial flat-rate Truck Shipping

Call us About Batteries 888-826-0939 we can really help.


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