The M1 unit came with 2 rechargeable lithium batteries. How long will one battery last approximately ? Is there a number of hours recommended before swapping to the second fully charged battery?
This depends on the protocol (higher frequencies draw more battery power) and the intensity setting (higher settings drain batteries faster). The M1 can run up to 6 or 8 hours on one battery charge, sometimes, but my advice, to get the best performance from a system operating at full power:
1-Always keep one battery on charge, ready to use.
2-Change batteries FREQUENTLY, every hour or two, whenever you think of it. The swap is designed to only take a few seconds, so swapping to get a fresh battery basically every time you think of it is a good practice.
That’s good advice!
I run my batteries dead every day multiple times. I’m thinking I might need a third battery. I fall asleep at night with the M1 running. I’ve found using the 4 coil attachment draws significant energy and the batteries go dead much faster. It’s just a good idea to make sure that the second unused battery is fully charged at all times.
Thanks! This is exactly the information I needed to know. About to try the M1 for the first time.
I’m running my M1 24/7 and always have several batteries charged up to allow me to swap them every hour or two, as Bob recommends. However, I’ve noticed that, after some time, these D-L188s become “fatter” and eventually fail to hold a charge for long enough, so I’m wondering if there’s a device that would allow me to monitor the batteries’ capacity so that I can ditch them before they reach the point of being unable to hold a good charge for the hour or two that I use them.
Well, the truth is that lithium batteries go bad generally much sooner than the manufacturers advertise. I have done everything I can to extend battery life, by limiting power surges from the power source, which accelerates battery degeneration for example. But the truth is that after a few hundred cycles, even lithium batteries start to go bad. The number of cycles varies by manufacturing batch, some good manufacturers occasionally turn out a bad batch, and there is really no way to detect this until batteries start failing. But here is what I do:
1- As soon as the batteries start to get a noticeable bulge, their internal chemistry is damaged, so they are on the brink of failure. Pay closer attention when you use batteries that have developed a bulge.
2- When you use batteries with a bulge, take note of how well they perform after a fresh charge. If they have a noticeably shorter life, or if they seem to have gone flat after just an hour of use (or less), then its time to replace that battery with a new one.
I did my best to find readily available, inexpensive lithium batteries for the M1, so replacements should not be excessively expensive or hard to find.