Recharging a 9v TENS Battery

If you have a TENS unit, you probably know that it is powered by a 9 volt heavy duty standard battery. There is also a chance that that battery is rechargeable. If that’s the case, you can reuse it after its energy has been depleted. For that you will need a 9V/AA/AAA Charger. As a matter of fact, the battery frequently needs to be charged before the unit’s initial use. In either case, here are a few things to keep in mind when the time comes to recharge your TENS device’s battery. 
The charger has to be plugged into a working 110 or 220/240v electrical outlet. Using an attachment that was not included with the charger itself may potentially lead to fire, shock or injury. Recharging a 9 volt battery is not an exact science, so you should stick to the charging time instructed by the manufacturer. Once that time has elapsed, remove the battery after unplugging the charger. After that, the battery can become discharged through constant use or disuse. A battery that has been idle for a sixty-day period or longer may lose its charge.

Overcharging a battery for up to 24 hours will not damage it, but continual overcharging may shorten the battery’s life. Remember to always store batteries in a fully charged condition. Recharge a battery as soon as you notice that it has been discharged. Be sure not to short the terminals of the battery, lest the battery becomes hot and then permanently damaged. Keep metal items such as keys and coins from coming into contact with batteries; that is, never store the batteries in your pocket of purse. Refrain from charging other types of batteries than the ones the charger is meant for. Keep the 9v battery away from flames, since that kind of exposure may cause it to explode. 
The 9V/AA/AAA Charger has an LED display to signify the charging status of the loaded batteries, and its small 96 x 48 x 32 dimensions make it ideal to carry around and provide a convenient solution to the problem of discharged batteries of multiple kinds. Its design, though lightweight, allows up to two AA or AAA batteries to be charged at the same time, or a single 9V battery. Unlike the actual batteries, you can safely put the charger in your purse; in fact, it was manufactured with that possibility in mind.

Related Read: 9V Heavy Duty Standard Battery Review