I’ve gone through so much money replacing alkaline batteries over the years because many metal detector manuals ask you to not use rechargeable ones. As the costs kept piling up, I decided to look into the reasons why the manufacturers ask you to use alkaline batteries instead, and after hours of research, I think I’ve got the answer.
So can you use rechargeable batteries in a metal detector? Yes, you can use rechargeable batteries in a metal detector. It is important that you use only good quality rechargeable batteries and recharge them on a good quality charger after each use.
I’ve researched what types of rechargeable batteries are best for metal detectors along with some other need-to-know based information that I’ll talk about below.
Why Manufacturers Say Rechargeable Batteries Shouldn’t Be Used
Modern metal detectors use electronic chips on them that allow the detector to work. On these chips, they use resistors to regulate the voltage from coming from the battery so it can be used and won’t mess up sensitive electronic parts. Along with protecting sensitive electronics, the resistors also allow the battery to last longer overall. So while you’ll see more voltage or milliamp hours advertised on an alkaline battery, the resistors on the chip won’t allow the full power of the battery to discharge at once.
Rechargeable batteries regulate their power and voltage based on the amount of charge left. While an alkaline battery will slowly die over time, and you’ll notice a change it the metal detector’s detection speed, volume, and depth, the rechargeable battery is more prone to just die with little to no warning. For example, a AA alkaline battery will come with 1.5volts, while a standard rechargeable AA battery will hold only 1.2volts at a full charge.
You’re already missing out on .3 volts, which doesn’t sound like a lot until you try it out for a day and realize the alkaline battery actually lasts longer as a whole.
This is important because it makes sense that companies have spent a lot of time developing the electronic circuitry to require a specific amount of power. Some older detectors used the old D batteries, while others use 9 volts, while many today use “battery packs” that ask for 4 or more AA batteries instead. As technology improves, the manufacturers get better with what type of batteries are required to make the metal detector work the most optimal way possible.
There isn’t really a reason why manufacturers recommend to use only alkaline batteries, but from my personal perspective, it looks like they would rather someone use a good quality alkaline that will last longer as a whole, than to have to recommend brands, charges, and charging instructions for a rechargeable battery instead. Kind of a “get out and have fun metal detecting” type of thing, versus telling you to do a lot of work maintaining your rechargeable batteries instead.
Why Most Choose Alkaline Batteries Instead of Rechargeable
Everyone wants to save money, and metal detecting can go through a lot of batteries. Many hobbyists have tried using rechargeable over the years, and they usually go back to standard alkaline batteries shorty later.
The reason most people choose alkaline batteries is because they just work, always. They require less maintenance, and you know that you’re not going to be in the middle of a field with a rechargeable battery that just plain dies without warning on you. On top of that, they can actually be cheaper than rechargeables if you know where and what types to buy.
I’ll let you in on a secret I learned recently. You can purchase “industrial” labeled batteries and save a ton of money on name brand batteries. These batteries are the exact same as what’s in the expensive retail packaging at your local store, but they come in cardboard/bulk packaging.
For example, the Energizer Industrial battery’s discharge and life are one of the absolute best, even over many more expensive Duracell types. The Energizer 9 volt, that you’d end up paying $8 USD + for a two pack, end up costing around $1-2 USD each in the bulk packaging of 12.
Finding the industrial / bulk packaged batteries aren’t the easiest for many locations, thankfully we have the internet. You can do a search on Google for “Energizer Industrial buy” for example. Here is a link to a reputable source for them:
Be careful where you buy your batteries from on the internet. For example, you never know what expiration dates you’ll get on Amazon. I’ve heard stories of batteries coming with less than a year of shelf-life left, or even just dead on arrival. I’d recommend a reputable source like I linked above, who’s business is selling batteries instead.
What about your pinpointer?
Although alkaline batteries are still preferred, things like your pin pointer can use rechargeable batteries just fine. The most popular pin pointer on the market today is the Pro Pointer by Garrett. Sadly, this pin pointer uses a 9 volt battery, and they can get quite expensive if you aren’t able to purchase a bulk industrial pack of them.
Using a rechargeable battery in your pin pointer won’t cause as many issues as using one in your metal detector, so feel free to get a couple rechargeable 9 volt batteries and a small charger for them. (This is a great idea for pretty much all other small electronics that require 9 volt batteries to save money).
What Rechargeable Batteries Last The Longest
So you’ve decided that you still want to use rechargeable batteries in your metal detector. The most important thing you you must do, is choose a name brand, good quality battery. Cheaper batteries will not last long, and they are prone to hurting your electronics if you leave them sitting inside.
The best rechargeable battery brands are Duracell and Energizer. Sure, there are some expensive “high end” batteries out there, but those two brands I mentioned in my experience provide the best results overall in all kinds of electronics, not just metal detectors.
The idea is to find a battery that won’t discharge itself over night and leave you with dead batteries if you take it off the charger. Look for “low self discharge” type. The “Energizer Recharge Universal” is a good all around battery that should serve you well. They’re a little pricey, but it’s worth it versus throwing something cheap at your electronics that could hurt them or take up a lot of time on a charger.
Rechargeable batteries are only as good as your charger. If you buy a low quality charger, you can’t trust it to deliver the correct charge to your batteries. This can destroy battery life or outright ruin them quickly. Good chargers are made by the big brands like Energizer or Duracell, or NiteCore. I personally prefer Nitecore battery chargers. Be wary of fake battery chargers, and purchase locally or through a reputable source online.
Overall, you’re going to get longer and maintenance-proof life out of a standard alkaline battery because they handle higher drain applications better. It comes down to if you’re willing to recharge your batteries after every metal detecting adventure to save some money, or if you’d rather just toss some batteries in and be change them much later after they weaken.
If I were asked for advice for a beginner, I would recommend them to get started with standard batteries first, instead of having to fiddle with maintaining their batteries. If they want to try to save some money in the long run and want to mess with the whole recharging, thing, then later down the road it’s definitely an option.