Notes On Handling Rechargeable Batteries; Specification - GRAUPNER ULTRAMAT 10 Operating Manual

16. Notes on handling rechargeable batteries

• Charging single NiCd or NiMH cells, and packs consisting of 1 ... 4 cells, presents the automatic
charge termination circuit with a difficult task. The voltage peak is quite small in such cases, and
it cannot be guaranteed that the cut-off circuit will work reliably. The automatic circuit may not be
triggered, or may not terminate at the correct time. For this reason it is important to carry out a
series of monitored test charge processes with single cells or small packs in order to establish
whether the charge is terminated reliably.
• Warm batteries offer much higher performance than cold ones, so don't be surprised if your batteries
don't seem so effective in the Winter.
• Overcharging and deep-discharging batteries leads to irreparable damage to the cells, and
permanently reduces their maximum performance and effective capacity.
• Never store batteries for a long time in an uncharged, discharged or part-charged state. Before storing
your batteries charge them up and check their state of charge from time to time.
• When purchasing batteries we recommend that you only buy good quality products. Start by charging
new packs at low rates, and work up gradually towards higher currents.
• Batteries should not be charged up until shortly before use, as they are then able to give you their
best performance.
• Do not solder directly to battery cells. The temperatures which occur during soldering can easily
damage the seals and safety valves of the cells. If this should happen, the battery may lose electrolyte
or dry out, and some of its potential performance will be lost.
• Charging any battery at high currents shortens the life expectancy of the pack. Don't exceed the
maximum values stated by the manufacturer.
• Overcharging inevitably reduces the capacity of the battery, so do not recharge a hot battery, or one
which has already been charged.
• Protect batteries from vibration, and do not subject them to mechanical stress or shock.
• Batteries can generate explosive gas (hydrogen) when on charge and when being discharged, so
it is important to provide good ventilation.
• Do not allow batteries to come into contact with water - explosion hazard.
• Never short-circuit battery contacts - explosion hazard.
• Do not open battery cells - corrosion hazard.
• It is best to „balance", or even up, the cells in Ni-Cd and Ni-MH battery packs by first discharging all
the cells separately and then charging up the pack. Individual cells can be discharged using certain
chargers, or they can be „bridged" using a 100 Ohm resistor over each individual cell in the pack.
• Please don't be surprised if your batteries are not as willing to accept charge in Winter as in Summer.
The ability of a cold cell to accept and store charge is much lower than that of a warm one.
• Battery disposal: exhausted batteries are not ordinary household waste, and you must not dispose
of them in the domestic rubbish. The retail outlet where you purchase your batteries should have a
battery recycling container for proper disposal. Trade outlets are obliged by law to accept exhausted
batteries for disposal.
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17. Specification

Battery:
Charge currents / power 100 mA to 5,0 A / max. 30W
Ni-Cd & Ni-MH batteries
Cell count 1 - 10 cells
Capacity min. 0,1 Ah to 4,0 Ah
Lithium batteries:
Cell count 1-4 cells
Cell voltage 3,6 V (LiIo) / 3,7 V (LiPo)
Capacity min. 0,2 Ah
General:
Operating voltage range 11,0 to 15 V
Car battery required 12 V, min. 24 Ah
Mains PSU required 12-14V, min. 5 A stabilised
No-load current drain approx. 100 mA
Low voltage cut-off approx. 10,0V
Weight approx. 1333 g
Dimensions approx. (LxBxH) 160 x 83 x 80 mm
All data assumes a car battery voltage of 12.7 V.
The stated values are guidelines, and may vary according to battery state, temperature etc.
1 ) When powered by a mains PSU, the charger will only operate correctly if the PSU is suitable in terms of voltage, stability, maximum load
capacity etc. You can avoid problems by using only the PSUs which we specifically recommend.
1)
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