Been buying batteries half your life? That doesn't mean you know all there is to know about them. Your ignorance could be costing you money and wasting your time. It's time to explode the battery myths!
Myth number one: You cannot recharge disposable alkaline batteries
This may have been a fact once upon a time, but whilst science has moved on, the battery manufacturers are not rushing to tell the consumer about it.
It clearly says on the sides of most alkaline batteries that they are not to be recharged; the warnings are fairly dire. "Batteries may explode" is what we're told, but is it true? Emphatically not.
Testers willing to put their lives 'at risk' by going ahead and recharging, found they were not even risking their eyebrows in the manner of some cartoon scientist, let alone their life. Even when using brief bursts of charge from a high-voltage car battery!
What testers did find was that the batteries would get hot if Over-charged, but the worst eventuality was a battery that gradually - and undramatically - split along one side, leaking a very small amount of acid. Not quite the firework display battery users have been warned of.
Whilst using a car battery for recharging alkaline batteries is not something any sensible person would recommend, there are alternatives. You definitely shouldn't use your standard recharger - these are not able to let you know when an alkaline battery is recharged which could lead to the overheating problem mentioned above - but devices are available designed specifically for recharging alkaline batteries. Some of these devices will charge Ni-Mh and Ni-Cds as well.
In the strictest sense, what is happening to the alkaline batteries is a 'recondition' rather than a 'recharge', giving a potential 90% power top-up to batteries low on energy. However, there is the potential for getting 10 or more times as much out of the battery's chemicals before it needs to be disposed of, it is both a money saver and more environmentally-friendly.
Care still needs to be taken: all batteries are capable of developing unseen faults which could see them split whilst charging, potentially damaging the charger or its surroundings. Some chargers will let you know if a battery is dead, but it is a good idea to purchase a separate battery tester to check the condition of all batteries you intend to recharge. This is important for alkaline batteries, as the battery will live longer the more frequently you recharge it. And wise for all other batteries, as even the best quality can develop faults.
If you have any doubts about the quality of the batteries you are using, it would be wisest to avoid placing reconditioned alkaline batteries in your most precious equipment.
Myth Two: Battery 'memory' is a real problem with rechargeable batteries
The concept of battery memory is not wrong, but it doesn't apply to all rechargeables, and it's a problem that is slowly becoming something from the past.
But first, what is 'battery memory'? Anyone with a rechargeable device may have noticed that the battery life seems to get shorter as the battery gets older. You may have had your own theory about why that is, but when it comes to Ni-Cd rechargeables, the short answer is 'crystal formation'.
In Ni-Cd batteries, as the battery ages crystals form inside. As the crystals get bigger, it gets harder for the charge to move beyond them. Eventually whole areas of the R59 battery become unreachable for both use and recharge. Failure to completely discharge the battery before recharging has been highlighted as one major cause of the problem.
Thankfully the problem isn't a killer: discharging the battery fully before starting a recharge usually sorts the problem. In fact, many recharging devices now do a full discharge. Manufacturers also continue to improve their batteries to get around the problem.
