How Long Does the Ember Mug Keep Coffee Hot?

If you're a coffee-lover, you understand the sheer pleasure that comes with every sip. The only downside of drinking coffee is it gets cold before you finish it. Luckily, smart mugs like Ember can keep coffee hot for extended periods of time. But how long exactly will the Ember Mug keep coffee hot for?

The Ember Mug 2 can keep coffee hot for 1.5 hours — specifically, at 135°F (57°C) for a 10 oz (295 mL) cup. The 14 oz (410 mL) mug can keep coffee hot for 80 minutes and the Ember Travel Mug keeps coffee hot for up to 3 hours. Ember mugs use lithium-ion batteries to power a heating element that keeps your drink hot.

This article will discuss in more detail the battery life of Ember mugs as well as how to extend it (there are some pretty cool ways to extend the battery life). I will also cover the different mugs available from Ember so you can decide the best one for you. 

The Battery Life of an Ember Mug

How long your drink stays hot in an Ember mug depends on a few different factors. Understanding these factors can help your drink stay hotter for longer. Meaning, your Ember should keep your drink hot right up until the very last sip.

The battery life for each Ember mug depends on the size and model of the mug. For example, the 12 oz (355 mL) Ember Travel Mug has a battery life of 3 hours, while the older Ember Mug 1 has a battery life of just one hour.

The newer version called the Ember Mug 2 (available at Amazon) has a newly designed charging coaster and promises a 50% longer battery life. 

To know more about the differences between each model, check out the following articles: 

Regardless of the model, an Ember mug's battery life can vary significantly due to factors such as: 

  • The initial temperature of the drink 
  • The surrounding room temperature
  • The temperature you want to maintain 
  • The addition of cold additives like milk or cream
  • Whether or not you use a lid on the mug

Ember mug temperatures range from 120°F to 145°F (48°C to 62.7°C).

A lower temperature setting generally prolongs battery life since it requires less power to sustain. In case you're wondering why the temperatures can't go any higher, read this article

If you place the Ember Mug on the charging coaster then it can keep you drink hot indefinitely without draining down the battery.

If you're worried about heating the Ember mug on the charging coaster too long, don't fret. The battery is designed not to overheat even if you leave it charging all day. It also has an automatic shut down feature when it doesn't detect any activity for 2 hours. 

As I'm sure you are aware, the older a Lithium-Ion battery is and the more cycles it's been through the less charge it'll hold. While I haven't noticed this yet on my Ember Mug I presume that over time it'll keep my coffee hot for shorter periods of time. Note that you can't replace the batteries if they break down, as this article explains. 

Make sure to charge your Ember mug properly to avoid damaging the batteries and the charging coaster. The process is pretty straightforward, but it's good to know the precautions to take nonetheless.  

How To Extend the Battery Life of an Ember Mug

The Ember mug's battery will usually last until your last sip (if you aren't too slow at drinking). However, you may want to use it for longer, or charge it as seldom as possible. Luckily, there's plenty you can do to extend the battery life of your Ember mug. 

Use a Lid

A lid will trap heat inside your Ember mug. Steam takes with it A LOT of heat, cooling down your drink quickly, which means the mug needs to work harder to keep your coffee hot.

By using a lid you'll get less steam escaping which means there's less strain on the batteries since they don't have to work as hard to keep the contents warm.

You can significantly increase the battery life just by using a lid. Fortunately, you have plenty of choices for the Best Ember Mug Lids. But there's only one that I really like and that's the PortaVia lid.

It sits snuggly inside the Ember Mug and is easy to drink from. It is affordable and actually fits in almost any coffee or tea mug. I love this product and highly recommend it.

See the latest price of the Portavia Silicone Lid at Amazon

It's worth noting that only the Ember Travel Mug comes with a lid upon purchase. However, as shown in the article above, you can also buy lids for the Ember Mug 2 separately. A lid is worth the extra cost because it helps you move around with your drink without worrying about spillage. 

Start With a Hot Drink

Your Ember mug's batteries will drain faster if the beverage is below your desired temperature. The colder the beverage is, the more energy it'll take for the batteries to heat it. Therefore, you can extend the battery life by pouring in an extra hot drink. 

Set the Mug to a Lower Temperature

A higher temperature setting also shortens the Ember mug's battery life. If you set the temperature between 130-135°F (54-57°C), you can still enjoy your beverage since that's the average temperature for coffee and tea. Also, the Ember mug’s default setting is 135°F (57°C), perfect for a latte. 

Don't Fill the Mug With More Than What You Need

When the mug is full, the batteries work harder to sustain the temperature of your beverage. 

Therefore, you can extend the battery life by keeping the mug half full. Besides, you can always get a refill if a half-full mug isn't enough for your caffeine fix. 

Keep the Mug Away From Ventilation

Placing the mug in ventilated areas lowers the temperature of your beverage. If you keep the mug away from air-conditioners, fans, or any place that lets in the air that can cool your drink, you can ensure your mug's battery life will last longer.

Pre-Heat The Mug With Boiling Water

This is a trick that I learned when working as a barista. We used to use it with keep cups that people brought into the cafe but you can use it for your Ember Mug too.

Simply fill up the Ember Mug with boiling water and leave for 15-30 seconds before discarding the boiling water down the sink and filling up the mug with your actual drink.

The boiling water will preheat the walls and base of the Ember Mug so they aren't cold and won't suck any heat out of your drink.

Wrap The Mug In A Cup Cosy

The Ember Mug keeps coffee hot with a heating element at the bottom but the sides are no insulated so it loses heat out the sides.

You can stop this by adding a mug warmer to the outside of your cup. It won't lose heat as quickly and therefore the battery will last longer.

Just make sure you find one that will fit even with the handle. Etsy is usually the best place to find good mug warmers.

See the latest variety of Mug Warmers at Etsy

Ember Mug Alternative: The Cauldryn Heated Mug

If you don't want to use an Ember mug for any reason, you can go for another popular heated coffee mug — namely, the one from Cauldryn. The Cauldryn heated mug has a wider temperature range at 32 to 212°F (0 to 100°C). That means it can heat cold beverages and even boil them if needed. 

Also, the Cauldryn mug has a battery life of 10 hours — significantly longer than that of the Ember mug. A couple of downsides are that the Cauldryn mug is slightly heavier and less aesthetically pleasing than its Ember counterpart. 

See the latest price of the Cauldryn Coffee Mug

Final Thoughts

The battery life of the Ember mug may seem relatively short, but there are many ways to extend its charge.

You can keep the mug on its charging coaster or a cozy, so you don't have to worry about the battery draining before you're done with your drink. For the most part, the Ember mug is the perfect companion for any coffee lover.