The batteries in our Puget Traverse Pro are lithium-ion (Li-ion) batteries.
Throw out everything that you thought you knew about battery charging. Lithium-ion batteries are a completely different animal from how other types of batteries work and are charged, maintained, and stored.
Many of us are familiar with the ubiquitous nickel-cadmium (NiCd) rechargeable batteries, which have been available to the public for many years. NiCd batteries, and nickel-metal hydride (NiMH) batteries can build up a "memory", which leads to loss of charge capacity. If these batteries are left in a semi-charged state, or repeatedly not given proper time to fully charge, they can build up a memory of these half-charged cycles. As a result when you go to "fully" charge them again, they will think that the 50% - 60%, etc., charge is a full 100% charge, and will only charge up to that 50%-60%, no matter how long you charge them. So with these types of batteries it is a good idea to "cycle" them from time to time, whereby you fully discharge them, then fully charge them a time or two. This helps these types of batteries forget the partial charge memory so that they can utilize full battery charge capability again. Lithium-ion batteries do not have this issue, so cycling the battery is not necessary. Simply charge as necessary.
When charging nickel based batteries it is best to do this in moderate temperature, and to make sure you complete a full charge cycle. When charging the lithium-ion battery in our Traverse Pro, it is recommended to do so at moderate temperature as well. You do not want to charge below freezing temperatures, and you do not want to expose the battery to excessive heat. Lithium-ion batteries do not need to be fully charged, and a partial charge is actually better for long-term storage purposes. It is advisable to discontinue charging and using a lithium-ion battery if it gets excessively warm, so please pay attention to the temperature of your battery throughout the use of your Puget Traverse Pro so you can notice when it is getting warmer than it should in typical use.
Nickel based batteries can be stored in a completely discharged state without any apparent negative side effects. However, this is not the case with lithium based batteries like those in the Puget Traverse Pro. With lithium based batteries it is best to store at a 40%-50% charge state, if you plan to store the lithium-ion battery for an extended period of time. It is also best to store the lithium-ion batteries in a dry location, at a cool room temperature. So in a way you can think of storing batteries like storing wine. Try to keep them around 55F, avoid light, and avoid temperature fluctuation. Avoid freezing, and as with both wine and batteries - heat kills. The higher the temperature the battery is stored, the sooner permanent capacity loss will occur. Under ideal conditions, lithium batteries can be stored for up to 10 years with only moderate capacity loss.
It's important to note that all batteries degrade over time, so the maximum charge capability will decrease, and all rechargeable batteries do have a limited number of charge cycles before they will no longer take another charge. Each battery is going to react a bit differently. Batteries, like children, have a mind of their own. While you may have seemingly "identical" batteries, it does not guarantee they will behave the same way. There is no silver bullet answer that will always work for a given battery type. Internal corrosion and other degrading effects play a part in batteries losing charge capacity over time.
Following these tips for battery care will help give you optimal performance from your Puget Traverse Pro lithium-ion battery.