The Bloating Of A (Razer) Mamba

The Razer Mamba is a fantastic gaming mouse. It feels great and its highly-precise laser sensor makes it a great joy to use, whether it's for gaming or for work. I can also choose to use it wirelessly, or attached to a high-speed USB cable. It has remained my favourite mouse for the last two years... until recently.

The Mamba may be good at many things but if it falls flat in the durability department. We used many Razer mice in the past, even reviewed a number of them, and as much as we love using them, they don't quite last as long as we would like.

Like on our older Razer mice, the Mamba's left button has started to malfunction - erroneously registering single clicks as double clicks. If that was not irritating enough, I noticed that the mouse was starting to "rock" a little - the base somehow was uneven. Very, very irritating.

At first, I thought it was caused by an accumulation of dirt on the teflon pads (or "feet") on the base on the mouse. Sure enough, there was plenty of dirt but even after cleaning off the muck, the mouse still "rocked". On closer inspection, I discovered something odd. Take a look at the picture on the left.

The battery door was jutting out! No wonder the base was uneven. This isn't normal as the battery door is designed to fit flush against the base. In fact, you can see the lock barely holding the door in place. The door looked like it was about to burst open. That's not a good sign at all.

I removed the battery door. At first glance, nothing seemed to be wrong. But on closer inspection, the Mamba's lithium-ion polymer battery didn't look quite right. It looked a little bloated. I popped the battery out and sure enough, the battery was bloated! These two pictures don't do justice to the amount of bloating.

The Mamba's lithium-ion polymer battery was originally 9 mm thick. In its current bloated condition though, it was 13 mm at the thickest. The increase of 4 mm may seem like nothing but it is certainly more than enough to cause the battery door to bulge out and make the Mamba rock in use.

What's more worrying is that the battery is now 44.4% thicker than it was designed to be. This battery has a tough plastic case, so a lot of hydrogen gas must have built up inside to cause so much bloating. If the battery continues to bloat, the highly pressurised gas inside will rupture the case, and cause the battery contents to leak out. The rupture may be violent enough to be considered "explosive". Certainly, you don't want to be in the vicinity when the battery ruptures!

The solution was simple enough - remove and replace the battery. Fortunately, the Mamba runs just as well using the USB cable. Look at how the battery door fits against the base after I removed the battery.

The Razer Mamba now glides very smoothly. No more rocking motion. No more tired wrist. Now, if only I can somehow fix the malfunctioning left button...

Please note that this is not a rant against the Razer Mamba. It's a great mouse. It's certainly not a rant against lithium-ion batteries either. We would just like to warn all Razer Mamba users, as well as users of other mice that use lithium-ion batteries, to watch out for bloated batteries. You do not want to wait until the battery ruptures. If the mouse doesn't feel quite right, check and see if the battery's bloated.

Don't visually inspect the battery in its bay. Pop it out to check. Our battery was obviously bloated on both sides, so it was easy to identify. It may not be so easy to spot batteries that have just started to bloat. Visually eyeballing the battery from the side helps, but you may have to compare the thickness of the battery in the center with the thickness at the sides.

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