Our FAQ answers some of the most common questions we receive regarding purchase, use and care of batteries. This section is monitored on a regular basis as new issues and questions from customers arise.
- How do I calculate a battery capacity?
- How long will my battery last?
- How long does it take to charge a battery?
- Do I need to fully discharge the battery each time before charging?
- What is the average shelf life of a battery?
- What would happen if I inserted a battery the wrong way round?
- How does cold weather affect batteries?
- How does hot weather affect batteries?
- What is the best battery for my particular device or application?
- What is the best brand (Duracell, GP Batteries, Ansmann etc) of battery?
- Are there any potential dangers when carrying loose batteries around?
- Do rechargeable batteries need to be charged before they are used?
- Can I replace my old NiCd batteries with NiMH batteries?
- Can I replace my old NiCd/NiMH/Lead Acid batteries with rechargeable Lithium-ion/Polymer?
- Can I mix batteries of different brands, chemistries and ages in my device or application?
Battery capacity = (current supplied × length of time supplied)
Example: A battery that can supply 3 amps for 5 hours has a capacity of 3 × 5 = 15Ah (Ampere-hour).
The run time of a cell or battery pack depends on a number of different factors. You can use simple electrical equations to give a rough idea of battery run time, but there are a number of other factors such as current drain of application, current peaks and troughs, voltage, environmental conditions that can impact on the final run time.
Basic calculation as follows:
|Battery Capacity (Ampere-hour)||= Battery Run Time (Hours)|
|Current Drain (Amps)|
Example: 15 Ampere-hour / 3 Amps = Battery Run Time of 5 hours
The charge time of a cell or battery pack depends on a number of different factors. A basic formula has been produced for you to calculate an estimate for the charge time of your battery:
Basic calculation as follows:
|Battery Capacity (Ampere-hour) × 1.2||= Battery Charge Time (Hours)|
|Output Current of Charger (Amps)|
Example: (10 Ampere-hour × 1.2) / 2.5 Amps = Battery Charge Time of 4.8 hours
It all depends on the particular chemistry of your battery. Lead Acid batteries should always be stored in a charged state and never be fully discharged regularly as this may cause damage and shorten the useful life of the battery. Nickel Metal Hydride and Nickel Cadmium use similar charging systems and it is generally considered that batteries should be fully discharged before they are charged again, they should however never be stored without any charge. It is recommended that around 30 – 40% charge is left in these batteries for storage and do not leave them unused for a long period of time.
Lithium Ion is a different charging system all together, it is important these batteries are charged correctly as they are the highest powered of all rechargeable chemistries. Suppliers and manufacturers should provide suitable guidelines for a charging regime when you purchase these batteries.
Typical shelf life is will vary according to the type of battery and depends on the storage conditions. Lithium batteries for example can have a shelf life of in excess of 15 years under ideal conditions.
Most consumer devices will generally have a diode or fuse to protect the electronic circuit if batteries are connected the wrong way round. Battery packs constructed by Cell Pack Solutions for use in industrial applications come with protection as standard, there will also generally be a connector or terminal attached to make sure the battery pack cannot possibly be connected in the device the wrong way. Batteries should be undamaged unless connecting them the wrong way round causes a short circuit.
Batteries are chemical systems and generally speaking, the colder it is, the slower the chemical reactions take. You may find that some batteries effectively freeze up and will not deliver the performance you expect. An important element of battery design is to understand the operational temperature range required by the application.
Generally speaking, the warmer the local temperature, the higher the self discharge rate of the battery. It is essential that you store your batteries in a cool, dry environment when not in use. It is also important to take into account the operational temperatures required, as some types may lose electrolyte at elevated temperatures.
There are a lot of similarities in terms of a battery’s performance in a consumer device or industrial application, however some batteries maybe more suitable than others – particularly when devices require a lot of power or needs to be on standby for a long period of time. Cell Pack Solutions provide guidance on our website and online shop but welcome calls from customers to tap into our large internal knowledge base.
We only deal with reputable world renowned manufacturers, where quality is of exceptionally high levels and we have full traceability for all of our products. All of the brands we sell are of similar high quality, although we do often get different levels of pricing so can provide customers with similar quality at better value.
Yes, batteries can be short circuited by metallic objects, such as coins and keys. When short circuited batteries can become very hot and potentially leak or vent causing injury or damage to items nearby. Please ensure battery terminals are protected or kept away from any potential short circuits.
Yes, rechargeable batteries are supplied with a low state of charge – maybe only 30% so will need fully charging before use. Manufacturers are now bringing out new ranges of rechargeable batteries which carry approximately 80% charge and are designated “ready to use”. Examples of such ranges are: Ansmann maxE, Duracell StayCharged and GP Batteries ReCyko.
We would always recommend replacing like for like, although there are some instances where NiMH can replace NiCd in applications. A lot depends on how the particular device or application charges the batteries. A new charger may also be needed as NiCd charging systems cannot charge NiMH batteries, but NiMH charging systems can charge both.
No, Lithium is a much more powerful chemistry and needs to be charged carefully to ensure correct working and safety of devices. Rechargeable lithium batteries have in built charge protection and specially designed chargers to allow cells to be charged when connected in parallel.
It is important that batteries in a device are all at the same capacity and voltage from the start. There is a potential for leakage and decreased run time if a mixture of different batteries are used. One battery could be completely discharged, where others could still have charge in making performance drop and leakage a possibility.