Anyone know how long Plainview 9volts last?

[thecavemankevin]

I bought several plainview's (170mha) 9volts about a year ago, but lately they seem to be loosing their charge real fast!

Any ideas? I thought theses weren't supposed to have memory problems like normal 9volts.

[Tim Taylor]

Are they Li-Ion or NiMH (my guess would me NiMH)? Li-Ion do not suffer from memory effect as such but have their own issues (price is a big one). Like NiCad, NiMH Batteries are also subject to memory effects, just at a slower rate. Much of the memory effect is dependent upon usage, the less you use a battery and the more you charge it the quicker it can develop a memory.

The type of charger also plays a large roll in the memory effect. If you use a standard 'constant current' charger it too can cause a memory effect. Chargers that incorporate a charge down circuit as well as trickle charge are the way to go, of course you could buy several cases of 9V's for the price of the charger

Most NiMH batteries are good for 1000 charges or so but a lot depends on the above circumstances. Try to use up as much energy from the batteries before charging. "Topping-off" a battery before a days use is probably one of the worst things you can do to either a NiCad or NiMH battery (though a NiMH will still vastly outlast a NiCad in this regard).

[sniper1rfa]

although, topping off a 9V before a days play may be neccessary, if your in a pinch, NiMH lose roughyl 60% capacity in about 30 days. :(

just cycle the battery a few times (drain it completely down to about 4 volts, then charge) and you should get some of your cpapcity back. although, it sounds like new batteries may be in order soon, as they arent going to last more than a couple years use. you could just have worn them out.

If cycled and charged correctly, niether NiCad nor NiMH should show much in the way of "memory." Because me mory is just crystalization of the chemistry, taking care of the battery will prevent it. :)

[thecavemankevin]

well, i know over the past few months i have always drained them, but i am not sure if i did that when i first bought them or not.

I cant find the charger right now, but it is the charger that the company that i bought them from said to use, and i know it takes about 20-24hours to charge.

here is the place i got them from
http://www.thomasdistributing.com/9v-nimh-batteries-chargers.htm

[sniper1rfa]

yeah, your batteries are just old. time for a new set.