In 2005, in anticipation of the restriction in the use of Ni-Cd batteries, Erich Kowalski began to redesign the full range of his Diving Torches, using an alternative power source. His conclusion was that Li-Ion batteries were the only realistic and best alternative to power his lamps. As a small manufacturer, producing entirely hand-built specialist lamps, this has been a very long and exhausting procedure, but I am pleased to say that it is nearing its end. The introduction of the new Maxum 620 and Maxum 1250 torches is the first stage of this transformation.
The notorious memory effect is often used to diminish the value of Ni-Cd batteries. The truth is; all other rechargeable batteries are affected as well, but not necessarily to the same extent. More important is the fact that the memory effect does not really play a role in respect of underwater torches. Other phenomena need to be considered with the memory effect. Imagine that you use an underwater lamp like a cordless phone. You recharge (not overcharge) it constantly, then use it for a short period of time (let us say a maximum of 5 minutes). Then, you recharge it again and repeat this cycle over and over again. After a certain period of time you would find a decline in the operating time of the lamp. The worst-case scenario will be that, after a period of six months, you can only use your torch for 5 minutes.
What happens in the cell? The chemical process takes place only in a small portion of the cell. The other portion is entirely unused and becomes inactive. As a rule, underwater torches are used much longer than for 5 minutes. The memory effect will not occur when the lamp is occasionally used for a only a few minutes or operated at 50% output. Often, a decline in the operating time is considered memory effect. But the decline in connection with underwater torches originates for other factors. If a lamp is in use for 1-3 weeks only and kept in store for the rest of the year, the cells are severely affected due to the occasional use.
Q. Why am I not getting the full burn time when I use the torch? A. The batteries of the torch should give approximately 300-500 recharges or last 3-5 years, but this does very much depend on the usage. The more regularly the torch is discharged and recharged, the more recharges you are likely to get. If a torch is left unused for long periods, the batteries become dormant and need to be revived.
Put the torch through a series of charge/recharge cycles, timing the discharge each time. If the burn time increases with each cycle, keep on doing it until the burn time recovers to the full specified time. If you do not achieve any significant improvement, please get in touch with Lighthouse.
Q. If I charge my torch and use it immediately and I get the full burn time, but if I leave it a few days, the burn time drops off dramatically. What's wrong? A. The batteries of the torch should give approximately 300-500 recharges or last 3-5 years.
I'm afraid that it is likely that your batteries are on their last legs. If you are happy to continue charging the night before you use the torch, you might find that it will last a few more months, before the batteries die altogether. When you need new batteries, contact Lighthouse Diving, where the new batteries have to be fitted by us, to maintain your guarantee.