Which Battery Is Best? Choosing Between Alkaline, Zinc, Lithium-Ion and Lead-Acid

AA batteries
© Eugene Brennan

What Type of Battery Should You Choose?

There are various types of batteries on the market today: different sizes, different technology, different voltages, rechargeable and single-use disposables. So how do you know which to use? This article gives some basic facts about the different types of batteries available.

Glossary

Cell. A device that produces a voltage from a chemical reaction and can source current to power electronic or electrical devices, appliances or tools. Examples are AA, AAA, C and D cells. Although these are technically called “cells,” they are commonly referred to as “batteries.”

Battery. A single cell can only produce a low voltage, typically 1.2, 1.5 or 3.6 volts. Batteries consists of several cells connected in series so that voltages add up. So, for instance, a 9-volt PP3 (MN1604) battery is composed of 6 flat cells stacked on top of each other, or 6 cylinders stacked side by side to produce 6 x 1.5 = 9 volts. The cells are encapsulated by an outer casing. A lead acid car battery is made of 6 cells in series to produce 12 volts.

Non-rechargeable or primary batteries. These are disposed of once they become “flat” and their stored energy has been used up.

Rechargeable secondary batteries. These can be “filled” with charge or energy and used again multiple times.

Capacity. The amount of charge a battery holds. It’s measured in milliamp-hours (mAh) or amp-hours (Ah). Energy capacity is also sometimes quoted in battery specs. This is typically given in watt-hours (Wh).

For more info on volts, current, amps, watts and electricity, see my easy-to-understand guide:

How to Understand Electricity: Volts, Amps and Watts Explained on Appliances.

Non-Rechargeable Batteries (Primary Cells)

Non-rechargeable or primary cells are available in all the standard sizes and voltages: AA, AAA, C, D and PP3 (MN1604). The nominal cell voltage is 1.5 volts and 9 volts for the small square PP3 type.

There are several widely available technologies:

• Zinc Carbon. These were the first, widely available non-rechargeable cells. They have a capacity between one quarter and one fifth that of alkaline cells. They have a relatively high internal resistance, and this makes them more suitable for low current drain devices such as radios, toys and low power torches. They don’t perform well at low temperatures, and high temperatures can dry out the electrolyte.
• Zinc Chloride. These are an improvement on zinc carbon having a 50% greater capacity, higher current output capacity and improved leak resistance. They also have better low temperature performance and longer shelf life.
• Alkaline. These have several advantages over zinc type batteries. Capacity is three to five times greater, they are able to provide a high current output, they have good high and low temperature performance and they have a long shelf life, losing about 5% of capacity per year. Alkaline batteries are the most expensive, however, compared to zinc cells, but the difference in price has reduced in the last 20 years as production has increased. The capacity of alkaline cells depends to a large degree on current load. At low currents, an AA cell can have a capacity of 3AH, but this can drop to less than 1 AH at current drain of about 1 amp (which is typical of high draw gadgets).
• Lithium. Lithium battery voltages range from 1.8 to 3.7 volts. The batteries are expensive compared to alkaline cells but have a higher energy storage density. They are suitable for high-current demand applications, and the output voltage is constant during discharge, unlike the sloping voltage characteristic of other primary cells. Lithium cells have a very long shelf life, and loss of capacity is only about 0.5% per year. There are several types:
  • 3-volt lithium cells in the CRV3 format which is like two AA cells side by side. This allows them to be used as drop-in replacements in devices which take two or four AA cells side by side.
  • 3-volt CR123A cells are often typically used to power digital cameras and wireless sensors in security alarm systems.
  • AA size lithium iron disulphide cells. These have a cell voltage of about 1.8 volts open circuit, dropping to around 1.7 volts when nearly empty. They have a shelf live of about 20 years.
  • 3-volt lithium coin cells are commonly used to power watches.
  • An advantage over alkaline cells is that they don't tend to leak which is important if they're used in expensive equipment. A battery leak can cause serious corrosion of metal connections and other parts.

CRV3 3 volt non-rechargeable lithium battery alongside an AA cell for size comparison.
Nitoshi, CC BY SA 2.5, 2.0 and 1.0 generic via Wikimedia Commons

Raimond Spekking, CC BY SA 4.0 via Wikimedia Commons

How Can You Test Batteries?

This is an inexpensive, easy-to-use universal battery checker suitable for 1.5-volt AA, AAA, C and D cells and also small, square 9-volt “PP3” (MN1604) style batteries, often used in digital multimeters. It’s suitable for alkaline, NiMH and NiCD cells but not lithium cells.

It indicates whether the battery is flat, low or fully charged on an analogue scale.

Universal battery tester available from Amazon
Amazon

High Power, High Drain Batteries

“High power,” “High Drain,” “Long Life” are terms often encountered on the packaging of AA, AAA, C, D and PP3 batteries, usually when sold in large packs in bargain basement stores. It’s important to realise that these are marketing terms, and the batteries may be zinc carbon or zinc chloride types with relatively low capacity. Make sure to check that alkaline is actually written on the packaging to get the best performance battery with high capacity and long shelf life.

Rechargeable Batteries (Secondary Cells)

Known as secondary cells, these are available in all the common sizes. The nominal cell voltage is 1.2 volts and 8.4 volts for the small square PP3(MN1604) cell.

• NiCd. Nickel cadmium batteries were the first commonly available rechargeable cells. NiCads suffer from a memory effect phenomenon which means that if you just keep topping up the battery rather than fully discharging it, the battery “remembers” the point from which it was topped up and will tend to lose capacity and discharge to this point. Loss of charge during storage is about 20% per month. The batteries have a low internal resistance and can source a high current on demand when used in moderate power devices. The voltage stays relatively constant during discharge.
• NiMH. Nickel metal hydride batteries are an improvement on NiCd. They have a higher capacity for a given size of battery but without exhibiting a memory effect phenomenon. They can also provide higher output for devices with a high current demand. Voltage is relatively steady during discharge. The disadvantage of NiMH batteries is that they lose charge relatively quickly, about 30% per month. LSD or low self discharge NiMH cells are available however.
• Rechargeable Lithium-Ion (Li-ion). These cells are used to make up the batteries for cordless tools, laptops, camcorders etc. The nominal cell voltage is normally between 3.2 V and 3.7 V, depending on the chemistry. Lithium-ion cells have a high energy density compared with most other rechargeable battery types, making them particularly suitable for portable equipment.
  Their size and voltage are somewhat different from AA and AAA cells, so they are not direct replacements for these types. However, some manufacturers now produce rechargeable lithium-ion batteries in AA and AAA formats, with internal electronics to regulate the output voltage to 1.5 V.
  Some tactical LED flashlights are designed to use CR123A or 18650 lithium cells. CR123A cells are normally non-rechargeable and have a nominal voltage of 3 V, whereas 18650 cells are rechargeable lithium-ion cells with a nominal voltage of 3.6–3.7 V. Rechargeable 16340 (RCR123A) cells are also available as alternatives to CR123A cells in compatible torches. Always check the torch manufacturer's specifications before substituting one type for another.
  Lithium-ion cells must be charged using a charger specifically designed for the particular chemistry and cell configuration.
• Lead Acid Gel Batteries. These are commonly found as the backup battery in alarm panels, however they are often used in high powered torches. They are relatively inexpensive compared to lithium cells. The nominal voltage is either 6 or 12 volts. Its important to use a proper three stage charger with these types of battery to maximise their lifespan. Also, unlike other types of battery, they can be damaged if the voltage is allowed to fall below 10 volts (for a 12 volt battery) for prolonged periods. “Yuasa” is a well known manufacturer of gel batteries.

Typical NiMh battery charger. Original image compressed.
Maxmust, CC BY SA 4.0 via Wikimedia Commons.

Pros and Cons of Rechargeable Batteries

Batteries can be rechargeable or non-rechargeable. Non rechargeable batteries can only be used once and then need to be replaced. Rechargeable batteries can be recharged up to 500 times.

Advantages

• Can be charged several hundred times before they become unable to hold a charge.
• They are able to source a high current output because of their low internal resistance. This means that they can power devices with a high current demand.

Disadvantages

• More expensive to buy than non-rechargeables but not hugely more expensive.
• Lose their charge over time through self-discharge even when not in a device. This can be up to 30% per month. So a battery is never fully charged when you go to use it , unless you keep it on constant trickle charge. Newer type NiMH batteries hold charge for longer. However, lithium-ion cells have very low self-discharge, so this problem is less of an issue
• Capacity of NiCd or NiMH rechargeable cells is less than that of alkaline cells.

Using Rechargeables as Replacements for Non-Rechargeables

Since the voltage of a NiMH rechargeable cell is about 1.2v compared to the 1.5 volts of a non rechargeable cell, this can cause problems in some devices. A device such as a torch will work ok since there is no electronic circuitry, and the torch will just run until the battery is flat.

Some electronic devices have voltage monitoring circuitry, which gives a low battery warning and turns off the device when the voltage falls to a certain level. Since NiMH batteries have a lower voltage, this will happen quicker resulting in lower effective duration of use on a charge. Also some equipment may not even work because of the lower voltage of these cells. Check your manual for advice.

Which Battery Lasts the Longest?

In order of highest capacity:

1. Lithium
2. Alkaline non-rechargeables
3. Zins chloride
4. Zinc carbon

Lithium batteries have the highest capacity and last the longest. Alkaline non-rechargeable batteries come second, having a long shelf life, low self-discharge and are inexpensive.

Using “Flat” AA Batteries

When a gadget indicates that the batteries are flat, this is often because electronics or software detects that the voltage is below a threshold level sufficient to run the device. However, the energy remaining is often adequate to run battery clocks for up to six months.

Remove Batteries From Equipment When Not in Use!

When batteries go flat, electrolyte becomes corrosive. Over time, this can eat through the casing of a battery and end up on battery terminals and circuit boards, potentially causing major damage to equipment. So if you aren’t going to be using your gadgets for a long period, it’s wise to remove the batteries before a leak occurs.

References

List of battery sizes on Wikipedia.

Disclaimer 

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2012 Eugene Brennan

Comments

Stephenmf on July 23, 2019:

I have a tv remote with AA zinc carbon batteries (low cost). When gone for a week or two the remote stops working, I reverse the two batteries and it works. This has happened many times on this and the ROKU remote. I am a bit confused and it is not the actual connection etc. I’m thinking that the almost flat batteries when gone is transferring most all the remaining charge to the second in-series battery. So the first battery

Eugene Brennan (author) from Ireland on July 23, 2019:

It wouldn’t make any difference because batteries are in series so the same current would be flowing through either of them, irrespective of which cell is flat. It’s possible that every time you remove batteries and replace them, the poor contact resistance between the terminals on the battery and in the remote control improves.

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