Take the 2-minute tour ×
Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It's 100% free, no registration required.

I am aware that attempting to charge a non-rechargeable battery is a terrible idea, and I have no intention of doing so. But supposing that, in a pinch, I needed to use non-rechargeable batteries in a device that originally came with rechargeable ones, and I don't use the charging cable the device came with while the non-rechargeable batteries are in use, could there still be a problem? How long would it take to manifest? Would it damage the device or batteries?

Sorry if this is off-topic, I'm thinking my question is along similar lines to this one.

share|improve this question

2 Answers 2

up vote 4 down vote accepted

RB = Rechargeable battery.
NRB = non rechargeable battery.
I'll limit the following to AA and AAA cells and then comment on others at the end.


  • When standard cell types such as AA, AAA PP3 (9V "transistor battery) and similar are used, the use of non-rechargeable batteries rather than rechargeable ones will almost never damage equipment. Essentially never in normal situations.

  • Almost no equipment that employs AA/AAA cells is made specifically for RB rather than NRB and it is expected that consumers will plug in NRB on some occasions.

  • The range of RB of NimH or NiCd is about 0.9V - 1.3V and the range of NRB such as Alkaline cells is about 0.9V - 1.6V.

  • So, at the high end a NRB may make (1.6-1.3)/1.3 x 100% = ~= 23% more voltage. This could conceivably cause a problem if tightly designed but is exceedingly unlikely to in practice.

  • A RB may output in excess of 10A for short periods under very heavy load and a NRB probably under 1/2 that in most cases BUT RB systems do not rely on such currents as they are not consistently available and cannot be maintained for long or for a large % of battery capacity.

"Standard" AA and AAA cells are expected to produce the voltages mentioned above. There are nn standard cells available that may give MORE voltage from a NRB than usual. eg primary Lithium Thionyl Chloride, Mercury, Lithium ion all MAY be found in AAA, AA, C, D sizes but they are rare an specialised and users are usually trained in the difference. Some of these are rechargeable and some are not.

Even then - as the voltages of th standard NRBs are LOWER than the special batteries the system is liable to simply treat them as "flat".

SO while some interesting an unusual situation MAY produce damage when very special batteries are expected , this is unlikely to happen and may never happen.


share|improve this answer
    
Thank you for your informative answer! –  Zev Chonoles Nov 18 '11 at 9:24
    
I'd recommend exercising more caution - electronic equipment specifically designed for NiCd or NiMH cells really may not tolerate the higher voltage of Alkalines and similar chemistries. There are a number of combinations where the lower voltage of the rechargeable results in the use of one or two more cells than would be used if the design was done for alkalines. –  Chris Stratton Nov 19 '11 at 5:50
    
@Chris Stratton - we are in complete agreement technically about the batteries - I note and you reiterate in different terms that an N cell pack may be up to about 25% higher if AA Alkaline are used. 8 cells is about the most you'll see (although I think I've seen 12 on very very very rare occasions). [ 8 cells x 1.6 = 12.8V] [8 x 1.3 = 10.4V] 1.6 and 1.3 ARE seen from Alkaline and NimH on occasion. Difference is 0.3 x 8 = 2.4V. –  Russell McMahon Nov 19 '11 at 9:15
    
@Chris Stratton - As I noted - it is possible that a system is so closely and poorly designed that it will wok OK on 10.4 and die on 12.8, but I genuinely do not recall EVER seeing a "rechargeable only" product with AA or AAA cells, or a consumer product that will not accept the extra 2.4V safely. –  Russell McMahon Nov 19 '11 at 9:16
    
If a design does not resort to a switching regulator or boost converter, and is optimized to be run at its highest safe voltage for maximum output, then the number of cells chosen for NiCd/NiMH will in many cases exceed the safe voltage if they are replaced with Alkalines. Generally this would only be done if the pack used solder-tab cells where they could not easily be replace with alkalines by accident. –  Chris Stratton Nov 19 '11 at 15:14

If your device will not try to charge those batteries, they will be fine. I assume you are talking about AA-type batteries, please check if battery voltage fits!

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.