The choice of the charge method and the type of charger (hereinafter referred to as a Battery Charger) determines maintaining high energy density of the battery, its safety and lifecycle. If not to choose the charging algorithm or the criteria of end of the charge correctly, it is possible either to have a constant low battery (when the capacity is lower than nominal) or to overcharge the battery. In the first case, the consumer does not use the battery fully on 100%, in the second - there is a real risk of an accident with all the sad consequences.
Since the design of internal battery chargers (built into the device) is usually the prerogative of the device developer, we suggest using the external battery chargers of various types.
External Battery Chargers for Ni-CD and Ni-MH batteries
Let us not dwell in detail on the methods of charging Ni-Cd and Ni-MH batteries. There is much information about it published on the Internet. Let us say only that nowadays the most correct and the safest method to charge the battery is to determine, so to say, the delta Voltage signal -ΔV (this is the voltage drop when the battery is fully charged) in Ni-Cd and Ni-MH batteries.
In our practice we use external Battery Chargers (with -ΔV signal detection) to charge Ni-Cd and Ni-MH batteries. There are models with power from 5W up to 60 W, both wall and desktop types. These Battery Chargers are used successfully to charge battery packs assembled from Ni-Cd and Ni-MH cells connected sequentially with capacity from 250mAh to 13000 mAh, with current from 250mA to 3000 mA.
• Battery Chargers for Ni-Cd and Ni-MH batteries (3-12 series connected cells) 6W (WHR models)
• Battery Chargers for Ni-Cd and Ni-MH batteries (3-12 series connected cells) 15W (W05N models)
These Battery Chargers have certificates of conformity of the GOST R system. They are manufactured in accordance with international standards CE, UL, FCC. They can be equipped with different power connectors according to the customer’s needs.
External Battery Chargers for Li-Ion and Li-Pol batteries
We will not write much here about the methods of charging Li-Ion and Li-Pol batteries. Note that the algorithm and methods of charging Li-Ion and Li-Pol batteries are identical. The only appropriate charging method is the so-called two-stage charge (CC-CV method) with a maximum voltage limit of charging.
In our practice we use external Battery Chargers (implementing the CC-CV charging method) to charge Li-ion and Li-Pol batteries. There are models with power from 6W up to 90 W, both wall and desktop types. These Battery Chargers are used successfully to charge battery packs assembled from Li-ion or Li-pol cells connected in sequence (and in parallel) with capacity from 400mAh to 25000mAh, with current from 500mA to 6000 mA.
• Battery Chargers for Li-Ion and Li-Pol batteries (2-6 series connected cells) (WHR60C models)
As an example, here is the Technical Specification on the battery charger, model Technical Specification on the battery charger SYB-L2S10M.
These Battery Chargers have certificates of conformity of the GOST R system. They are manufactured in accordance with international standards CE, UL, FCC. They can be equipped with different power connectors according to the customer’s needs.
This information should be supplemented by some refinements. The above-mentioned Battery Chargers (intended to charge Li-ion and Li-Pol batteries) are designed for the battery packs with PCM (Protection Circuit Modules).
The Li-Ion and Li-Pol battery protection boards protect each battery cell from over-discharging, and, what is more important, from overcharging, that can lead to a battery failure.
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