Lead Acid Batteries – Pros & Cons
Since the 1800s, the lead-acid battery has been around and is probably the oldest kind of battery design available. But lead acids remain very common despite the introduction of newer battery technologies. Lead-acid batteries account for about 40 percent of the world’s batteries sold. This popularity is due in part to the strength of lead-acid batteries, and the low cost them.
- Available Readily. Just about everywhere you find car parts, you can find a lead-acid battery.
- Relatively inexpensive – depending on form and efficiency, a Group 31 size deep cycle lead-acid battery with 100 percent capacity will cost $150 – $300.
- Lead acids are stable and robust – they are designed to take on a lot of violence, particularly in automotive applications where vibration can be a severe problem.
- They’re big (relatively). Lead-acids have low energy to weight ratio as compared to LiFePO4 batteries.
- Shorter lifespan and cycle life, especially when deeply discharged, than LiFePO4 batteries.
- Discharging lead-acid deep-cycle batteries below 20 percent (and often 50 percent) permanently decreases the battery’s power.
- There are some questions regarding the discharge of gas and acid leakage, but this is relatively uncommon on newer maintenance-free batteries.
High current loads decrease rated capacity rapidly… most deep-cycle lead-acid batteries discharge steadily and slowly over 20+ hours. If the time frame is lowered, the output rating decreases.
Finally, it is essential to remember that there are numerous types of batteries with lead-acid, each of which has its pros and cons. The most expensive are gel and AGM batteries, but they are also the most durable and the longest. In maintenance-free setups, “Wet” batteries are available, or they can need periodic refilling. The benefit of these wet batteries is lower costs, and they also have more energy capacity if they are the kind that needs maintenance.
Batteries With Lithium Iron Phosphate – Pros & Cons
Although there are quite a few different lithium-ion batteries (it seems like more are invented every day), lithium iron phosphate batteries have been around for a few generations ). In automotive applications, this specific battery chemistry is standard, as it is robust, reliable, and well-suited for starting automobiles. Lithium iron phosphate deep-cycle batteries often strike a strong balance between energy storage and lifespan. For years of usage, they can be counted on.
- Depending on discharge depth and assuming that the cycle limit does not kill the battery first, long life span (5-10 years) vs. lead-acid (1-3 years)
- Compared to similarly-sized lead-acid batteries, longer cycle life can range from 200 to 1000 cycles, as LiFePO4 batteries last 1,000 to 3,000 charge and discharge cycles (again, assuming that the depth of battery discharge is within recommended limits both types).
- LiFePO4 batteries are less prone to discharge depth issues. A LiFePO4 battery can be dropped without long-term damage to 20 percent of the charge. If they are discharged by more than 50 percent, most lead-acid batteries lose power or cycle life.
- Lighter than batteries of lead-acid.
- LiFePO4 batteries are arguably more eco-friendly than lead-acid.
- Relatively safe – the chances are very low for a “thermal runaway” (aka battery fire). The same can not be said of the other chemistries of lithium ions.
- LiFePO4 batteries are, as described, expensive.
- It is challenging to locate LiFePO4 batteries. The bulk must be acquired online.
- Susceptible to damage from overcharging (if you want to optimize their existence, it’s essential to use a charging system designed for LiFePO4 batteries).
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